CVE-2021-33620

mediumpriority · attend · 54EPSS 0.796 · 100 %ileDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

79.6% (100th) EPSS

CVSS 4 · medium

Is it mine?

55 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

Squid before 4.15 and 5.x before 5.0.6 allows remote servers to cause a denial of service (affecting availability to all clients) via an HTTP response. The issue trigger is a header that can be expected to exist in HTTP traffic without any malicious intent by the server.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

Fixedlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.src (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-debuginfo-0:1.0.1-2.module+el8.1.0+4044+36416a77.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-debuginfo-0:1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-debuginfo-0:1.0.1-2.module+el8.1.0+4044+36416a77.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-debuginfo-0:1.0.1-2.module+el8.1.0+4044+36416a77.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-debugsource-0:1.0.1-2.module+el8.1.0+4044+36416a77.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-debugsource-0:1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-debugsource-0:1.0.1-2.module+el8.1.0+4044+36416a77.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-debugsource-0:1.0.1-2.module+el8.1.0+4044+36416a77.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-devel-0:1.0.1-2.module+el8.1.0+4044+36416a77.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-devel-0:1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-devel-0:1.0.1-2.module+el8.1.0+4044+36416a77.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedlibecap-devel-0:1.0.1-2.module+el8.1.0+4044+36416a77.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.src (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-debuginfo-7:4.15-1.module+el8.5.0+11469+24c223d9.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-debuginfo-7:4.15-1.module+el8.5.0+11469+24c223d9.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-debuginfo-7:4.15-1.module+el8.5.0+11469+24c223d9.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-debuginfo-7:4.15-1.module+el8.5.0+11469+24c223d9.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-debugsource-7:4.15-1.module+el8.5.0+11469+24c223d9.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-debugsource-7:4.15-1.module+el8.5.0+11469+24c223d9.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-debugsource-7:4.15-1.module+el8.5.0+11469+24c223d9.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Fixedsquid-debugsource-7:4.15-1.module+el8.5.0+11469+24c223d9.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 After installing this update, the squid service will be restarted automatically.
https://access.redhat.com/errata/RHSA-2021:4292
Workaroundlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.src (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-0:1.0.1-2.module+el8.1.0+4044+36416a77.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-debuginfo-0:1.0.1-2.module+el8.1.0+4044+36416a77.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-debuginfo-0:1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-debuginfo-0:1.0.1-2.module+el8.1.0+4044+36416a77.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-debuginfo-0:1.0.1-2.module+el8.1.0+4044+36416a77.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-debugsource-0:1.0.1-2.module+el8.1.0+4044+36416a77.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-debugsource-0:1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-debugsource-0:1.0.1-2.module+el8.1.0+4044+36416a77.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-debugsource-0:1.0.1-2.module+el8.1.0+4044+36416a77.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-devel-0:1.0.1-2.module+el8.1.0+4044+36416a77.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-devel-0:1.0.1-2.module+el8.1.0+4044+36416a77.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-devel-0:1.0.1-2.module+el8.1.0+4044+36416a77.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundlibecap-devel-0:1.0.1-2.module+el8.1.0+4044+36416a77.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.src (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-7:4.15-1.module+el8.5.0+11469+24c223d9.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-debuginfo-7:4.15-1.module+el8.5.0+11469+24c223d9.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-debuginfo-7:4.15-1.module+el8.5.0+11469+24c223d9.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-debuginfo-7:4.15-1.module+el8.5.0+11469+24c223d9.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-debuginfo-7:4.15-1.module+el8.5.0+11469+24c223d9.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-debugsource-7:4.15-1.module+el8.5.0+11469+24c223d9.aarch64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-debugsource-7:4.15-1.module+el8.5.0+11469+24c223d9.ppc64le (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-debugsource-7:4.15-1.module+el8.5.0+11469+24c223d9.s390x (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Workaroundsquid-debugsource-7:4.15-1.module+el8.5.0+11469+24c223d9.x86_64 (squid:4) as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04mediumAV:N/AC:L/Au:S/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 8 · impact 2.9

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.16.5mediumAV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.16.5mediumCVSS:3.1/AC:L/AV:N/A:H/C:N/I:N/PR:L/S:U/UI:Nsecondary · ENISA EU

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · cve@mitre.org USexploitability 2.8 · impact 3.6

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:Hsecondary · CVSS-BT (t0sche)

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · Red Hat Product Security US

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-20USCWE-20US

affected products (55)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Open Source Squid <4.15all versionscert_bundDE
Open Source Squid <5.0.6all versionscert_bundDE
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
Open Source Squid< 4.15cert_bundDE
Open Source Squid< 5.0.6cert_bundDE
n/a n/a≤ n/aenisa_euvdEU
Squid Software Foundation Squid≤ 4.15fstec_bduRU
Squid Software Foundation Squid5.0 → 5.0.6fstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
ООО «Ред Софт» РЕД ОС≤ 7.3fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.6 «Смоленск»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition для «Эльбрус»≤ 8.1 «Ленинград»fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 9fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 8fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 10fstec_bduRU

showing 20 of 55

advisories (2)

Vendor and ecosystem advisories describing this.

RHSA-2021:4292Red Hat Security Advisory: squid:4 security, bug fix, and enhancement update2021-11-09csaf · redhat_csafUS
An update for the squid:4 module is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
WID-SEC-W-2022-0642Squid: Schwachstelle ermöglicht Denial of ServiceDeutsch2021-05-30csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in Squid ausnutzen, um einen Denial of Service Angriff durchzuführen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund redhat_csaf NVD CVE.org MITRE

published 2021-05-28modified 2026-06-17

related (25,176)

Related entries.

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+25171 more

references (33)

External citations — patches, advisories, analysis.

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