CVE-2016-2569

mediumpriority · attend · 51EPSS 0.312 · 98 %ileexploit · PoCEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

31.2% (98th) EPSS

CVSS 5 · medium

Is it mine?

168 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

Squid 3.x before 3.5.15 and 4.x before 4.0.7 does not properly append data to String objects, which allows remote servers to cause a denial of service (assertion failure and daemon exit) via a long string, as demonstrated by a crafted HTTP Vary header.

remediations

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

A vendor fix is available.

Fixedsquid-7:3.5.20-2.el7.aarch64 as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-7:3.5.20-2.el7.ppc64 as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-7:3.5.20-2.el7.ppc64le as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-7:3.5.20-2.el7.s390x as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-7:3.5.20-2.el7.src as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-7:3.5.20-2.el7.src as a component of Red Hat Enterprise Linux Workstation (v. 7)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-2016:2600
Fixedsquid-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Workstation (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.aarch64 as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.aarch64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.ppc64 as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.ppc64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.ppc64le as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.ppc64le as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.s390x as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.s390x as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Workstation (v. 7)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-2016:2600
Fixedsquid-debuginfo-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Workstation Optional (v. 7)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-2016:2600
Fixedsquid-migration-script-7:3.5.20-2.el7.aarch64 as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-migration-script-7:3.5.20-2.el7.ppc64 as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-migration-script-7:3.5.20-2.el7.ppc64le as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-migration-script-7:3.5.20-2.el7.s390x as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-migration-script-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Server (v. 7)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-2016:2600
Fixedsquid-migration-script-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Workstation (v. 7)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-2016:2600
Fixedsquid-sysvinit-7:3.5.20-2.el7.aarch64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-sysvinit-7:3.5.20-2.el7.ppc64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-sysvinit-7:3.5.20-2.el7.ppc64le as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-sysvinit-7:3.5.20-2.el7.s390x as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-sysvinit-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Server Optional (v. 7)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-2016:2600
Fixedsquid-sysvinit-7:3.5.20-2.el7.x86_64 as a component of Red Hat Enterprise Linux Workstation Optional (v. 7)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-2016:2600

cvss

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

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Psecondary · FSTEC (BDU) RU

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Psecondary · Red Hat Product Security US

v3.07.1highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Psecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-20USCWE-617US

exploits (1)

Public proof-of-concept and weaponised exploit code.

amit-raut/CVE-2016-2569Squid 3.x before 3.5.15 and 4.x before 4.0.7 does not properly append data to String objects, which allows remote servers to cause a denial of service (assertion failure and daemon exit) via a long string, as demonstrated by a crafted HTTP Vary header.PoC · poc_in_github

affected products (168)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
Squid Software Foundation Squid3.0 → 3.5.15fstec_bduRU
Squid Software Foundation Squid4.0.1 → 4.0.7fstec_bduRU
squid-cache squid= 3.0nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable1nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable10nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable11nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable12nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable13nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable14nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable15nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable16nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable17nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable18nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable19nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable2nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable20nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable21nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable22nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable23nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*

showing 20 of 168

advisories (1)

Vendor and ecosystem advisories describing this.

RHSA-2016:2600Red Hat Security Advisory: squid security, bug fix, and enhancement update2016-11-03csaf · redhat_csafUS
An update for squid is now available for Red Hat Enterprise Linux 7. 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.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd redhat_csaf NVD CVE.org MITRE

published 2016-02-27modified 2026-06-17

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+25168 more

references (25)

External citations — patches, advisories, analysis.

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