CVE-2024-23638

mediumpriority · attend · 47EPSS 0.601 · 99 %ileDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

60.1% (99th) EPSS

CVSS 6.5 · medium

Is it mine?

35 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-24

Squid is a caching proxy for the Web. Due to an expired pointer reference bug, Squid prior to version 6.6 is vulnerable to a Denial of Service attack against Cache Manager error responses. This problem allows a trusted client to perform Denial of Service when generating error pages for Client Manager reports. Squid older than 5.0.5 have not been tested and should be assumed to be vulnerable. All Squid-5.x up to and including 5.9 are vulnerable. All Squid-6.x up to and including 6.5 are vulnerable. This bug is fixed by Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives. As a workaround, prevent access to Cache Manager using Squid's main access control: `http_access deny manager`.

remediations

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

A vendor fix is available.

Fixedsquid-7:5.5-13.el9_4.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-7:5.5-13.el9_4.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-7:5.5-13.el9_4.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-7:5.5-13.el9_4.src as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-7:5.5-13.el9_4.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-debuginfo-7:5.5-13.el9_4.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-debuginfo-7:5.5-13.el9_4.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-debuginfo-7:5.5-13.el9_4.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-debuginfo-7:5.5-13.el9_4.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-debugsource-7:5.5-13.el9_4.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-debugsource-7:5.5-13.el9_4.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-debugsource-7:5.5-13.el9_4.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Fixedsquid-debugsource-7:5.5-13.el9_4.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)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
https://access.redhat.com/errata/RHSA-2024:4861
Workaroundsquid-7:5.5-13.el9_4.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-7:5.5-13.el9_4.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-7:5.5-13.el9_4.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-7:5.5-13.el9_4.src as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-7:5.5-13.el9_4.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-debuginfo-7:5.5-13.el9_4.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-debuginfo-7:5.5-13.el9_4.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-debuginfo-7:5.5-13.el9_4.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-debuginfo-7:5.5-13.el9_4.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-debugsource-7:5.5-13.el9_4.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-debugsource-7:5.5-13.el9_4.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-debugsource-7:5.5-13.el9_4.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager
Workaroundsquid-debugsource-7:5.5-13.el9_4.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
Restrict entry to Cache Manager through Squid's primary access control: http_access deny manager

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

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/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · security-advisories@github.comexploitability 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-672USprimaryCWE-672USCWE-825USCWE-825USCWE-825US

affected products (35)

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:-
Fedora Linuxall versionscert_bundDEcpe:/o:fedoraproject:fedora:-
Open Source Squid <6.6all versionscert_bundDE
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
RESF Rocky Linuxall versionscert_bundDEcpe:/o:resf:rocky_linux:-
RESF Rocky Linux 8all versionscert_bundDEcpe:/o:resf:rocky_linux:8
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< 6.6cert_bundDE
squid-cache squidall versionsenisa_euvdEU
squid-cache squid≤ < 6.6enisa_euvdEU
Squid Software Foundation Squid5.0 → 5.9fstec_bduRU
Squid Software Foundation Squid6.0 → 6.6fstec_bduRU
АО «ИВК» АЛЬТ СП 10all versionsfstec_bduRU
АО «НТЦ ИТ РОСА» РОСА ХРОМ≤ 12.4fstec_bduRU
ООО «Ред Софт» РЕД ОС≤ 7.3fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 4.7fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.7fstec_bduRU

showing 20 of 35

advisories (2)

Vendor and ecosystem advisories describing this.

RHSA-2024:4861Red Hat Security Advisory: squid security update2024-07-25csaf · redhat_csafUS
An update for squid is now available for Red Hat Enterprise Linux 9. 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-2024-0180Squid: Schwachstelle ermöglicht Denial of ServiceDeutsch2024-01-23csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in Squid ausnutzen, um einen Denial of Service Angriff durchzuführen.

also known as (3)

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 2024-01-24modified 2026-06-17

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references (29)

External citations — patches, advisories, analysis.

scry

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