CVE-2011-4096

mediumpriority · track · 33EPSS 0.372 · 99 %ileEUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

37.2% (99th) EPSS

CVSS 5 · medium

Is it mine?

76 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · redhat_csaf

EPSS · scored 2026-10-28

The idnsGrokReply function in Squid before 3.1.16 does not properly free memory, which allows remote attackers to cause a denial of service (daemon abort) via a DNS reply containing a CNAME record that references another CNAME record that contains an empty A record.

remediations

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

A vendor fix is available.

Fixedsquid-7:3.1.10-1.el6_2.1.i686 as a component of Red Hat Enterprise Linux Server (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-7:3.1.10-1.el6_2.1.i686 as a component of Red Hat Enterprise Linux Workstation (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-7:3.1.10-1.el6_2.1.ppc64 as a component of Red Hat Enterprise Linux Server (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-7:3.1.10-1.el6_2.1.s390x as a component of Red Hat Enterprise Linux Server (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-7:3.1.10-1.el6_2.1.src as a component of Red Hat Enterprise Linux Server (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-7:3.1.10-1.el6_2.1.src as a component of Red Hat Enterprise Linux Workstation (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-7:3.1.10-1.el6_2.1.x86_64 as a component of Red Hat Enterprise Linux Server (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-7:3.1.10-1.el6_2.1.x86_64 as a component of Red Hat Enterprise Linux Workstation (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-debuginfo-7:3.1.10-1.el6_2.1.i686 as a component of Red Hat Enterprise Linux Server (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-debuginfo-7:3.1.10-1.el6_2.1.i686 as a component of Red Hat Enterprise Linux Workstation (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-debuginfo-7:3.1.10-1.el6_2.1.ppc64 as a component of Red Hat Enterprise Linux Server (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-debuginfo-7:3.1.10-1.el6_2.1.s390x as a component of Red Hat Enterprise Linux Server (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-debuginfo-7:3.1.10-1.el6_2.1.x86_64 as a component of Red Hat Enterprise Linux Server (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791
Fixedsquid-debuginfo-7:3.1.10-1.el6_2.1.x86_64 as a component of Red Hat Enterprise Linux Workstation (v. 6)redhat_csaf
Before applying this update, make sure all previously-released errata relevant to your system have been applied. This update is available via the Red Hat Network. Details on how to use the Red Hat Network to apply this update are available at https://access.redhat.com/kb/docs/DOC-11259
https://access.redhat.com/errata/RHSA-2011:1791

cvss

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

5.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.3–5

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

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:P/E:Hsecondary · CVSS-BT (t0sche)

v2.03.3lowAV:A/AC:L/Au:N/C:N/I:N/A:Psecondary · Red Hat Product Security US

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-399USprimary

affected products (76)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
squid-cache squid≤ 3.1.15nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*
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:*:*:*:*:*:*:*:*
squid-cache squid= 3.0.stable24nvdUScpe:2.3:a:squid-cache:squid:*:*:*:*:*:*:*:*

showing 20 of 76

advisories (1)

Vendor and ecosystem advisories describing this.

RHSA-2011:1791Red Hat Security Advisory: squid security update2011-12-06csaf · redhat_csafUS
An updated squid package that fixes one security issue is now available for Red Hat Enterprise Linux 6. The Red Hat Security Response Team has rated this update as having moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link in the References section.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd redhat_csaf NVD CVE.org MITRE

published 2011-11-17modified 2026-06-16

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+3721 more

references (28)

External citations — patches, advisories, analysis.

scry

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