Description
Squid is a web proxy cache. Starting in version 3.5.27 and prior to version 6.8, Squid may be vulnerable to a Denial of Service attack against HTTP Chunked decoder due to an uncontrolled recursion bug. This problem allows a remote attacker to cause Denial of Service when sending a crafted, chunked, encoded HTTP Message. This bug is fixed in Squid version 6.8. In addition, patches addressing this problem for the stable releases can be found in Squid's patch archives. There is no workaround for this issue.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| squid-cache | squid | >= 3.5.27, < 6.8 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | squid | 6.8-1 | — |
| Debian 13 | squid | 6.8-1 | — |
| Debian 12 | squid | 5.7-2+deb12u1 | — |
| Debian 11 | squid | 4.13-10+deb11u4 | DLA-4083-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | squid | 6.6-1ubuntu4 | — |
| Ubuntu 22.04 LTS | squid | 5.7-0ubuntu0.22.04.4 | USN-6728-1 |
| Ubuntu 20.04 LTS | squid | 4.10-1ubuntu1.10 | USN-6728-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | squid3 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | squid3 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | squid | 7:5.5-6.el9_3.8 | RHSA-2024:1376 |
| RHEL 8 | libecap +1 | 1.0.1-2.module+el8.9.0+19703+a1da7223 | RHSA-2024:1375 |
| RHEL 8 | squid | 7:4.15-7.module+el8.9.0+21530+59b09a5b.10 | RHSA-2024:1375 |
Show 10 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.2 EUS | squid | 7:5.5-5.el9_2.6 | RHSA-2024:1515 |
| RHEL 9.0 EUS | squid | 7:5.2-1.el9_0.6 | RHSA-2024:1833 |
| RHEL 8.8 EUS | libecap +1 | 1.0.1-2.module+el8.1.0+4044+36416a77 | RHSA-2024:2822 |
| RHEL 8.8 EUS | squid | 7:4.15-6.module+el8.8.0+21509+962c493b.6 | RHSA-2024:2822 |
| RHEL 8.6 EUS | libecap +1 | 1.0.1-2.module+el8.1.0+4044+36416a77 | RHSA-2024:1479 |
| RHEL 8.6 EUS | squid | 7:4.15-3.module+el8.6.0+21519+58cab4c1.6 | RHSA-2024:1479 |
| RHEL 8.4 TUS | libecap +1 | 1.0.1-2.module+el8.1.0+4044+36416a77 | RHSA-2024:1832 |
| RHEL 8.4 TUS | squid | 7:4.11-4.module+el8.4.0+21523+3cc98f8b.8 | RHSA-2024:1832 |
| RHEL 8.4 E4S | libecap +1 | 1.0.1-2.module+el8.1.0+4044+36416a77 | RHSA-2024:1832 |
| RHEL 8.4 E4S | squid | 7:4.11-4.module+el8.4.0+21523+3cc98f8b.8 | RHSA-2024:1832 |
| RHEL 8.4 AUS | libecap +1 | 1.0.1-2.module+el8.1.0+4044+36416a77 | RHSA-2024:1832 |
| RHEL 8.4 AUS | squid | 7:4.11-4.module+el8.4.0+21523+3cc98f8b.8 | RHSA-2024:1832 |
| RHEL 8.2 TUS | libecap +1 | 1.0.1-2.module+el8.1.0+4044+36416a77 | RHSA-2024:2777 |
| RHEL 8.2 TUS | squid | 7:4.4-8.module+el8.2.0+21527+aa63d5ff.9 | RHSA-2024:2777 |
| RHEL 8.2 E4S | libecap +1 | 1.0.1-2.module+el8.1.0+4044+36416a77 | RHSA-2024:2777 |
| RHEL 8.2 E4S | squid | 7:4.4-8.module+el8.2.0+21527+aa63d5ff.9 | RHSA-2024:2777 |
| RHEL 8.2 AUS | libecap +1 | 1.0.1-2.module+el8.1.0+4044+36416a77 | RHSA-2024:2777 |
| RHEL 8.2 AUS | squid | 7:4.4-8.module+el8.2.0+21527+aa63d5ff.9 | RHSA-2024:2777 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 9 | squid | 7:5.5-6.el9_3.8 | ALSA-2024:1376 |
| AlmaLinux 8 | libecap +1 | 1.0.1-2.module_el8.6.0+2741+01592ae8 | ALSA-2024:1375 |
| AlmaLinux 8 | squid | 7:4.15-7.module_el8.9.0+3749+dbf371ed.10 | ALSA-2024:1375 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | libecap | 1.0.1-2.module+el8.9.0+1437+df5ea8f0 | RLSA-2024:1375 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | squid | 5.7-150400.3.26.1 | SUSE-SU-2024:1113-1 |
| SLES 15 SP4 | squid | 5.7-150400.3.26.1 | SUSE-SU-2024:1113-1 |
| SLES 15 SP3 | squid | 4.17-150000.5.52.1 | SUSE-SU-2024:1114-1 |
| SLES 15 SP2 | squid | 4.17-150000.5.52.1 | SUSE-SU-2024:1114-1 |
| SLES 12 SP5 | squid | 4.17-4.44.1 | SUSE-SU-2024:1115-1 |
Show 10 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP4 | squid | 5.7-150400.3.26.1 | SUSE-SU-2024:1113-1 |
| SLES for SAP 15 SP3 | squid | 4.17-150000.5.52.1 | SUSE-SU-2024:1114-1 |
| SLES for SAP 15 SP2 | squid | 4.17-150000.5.52.1 | SUSE-SU-2024:1114-1 |
| SLES for SAP 12 SP5 | squid | 4.17-4.44.1 | SUSE-SU-2024:1115-1 |
| SLE HPC 15 SP4 | squid | 5.7-150400.3.26.1 | SUSE-SU-2024:1113-1 |
| SLE HPC 15 SP3 | squid | 4.17-150000.5.52.1 | SUSE-SU-2024:1114-1 |
| SLE HPC 15 SP2 | squid | 4.17-150000.5.52.1 | SUSE-SU-2024:1114-1 |
| SUSE Manager Server 4.3 | squid | 5.7-150400.3.26.1 | SUSE-SU-2024:1113-1 |
| SUSE Manager Proxy 4.3 | squid | 5.7-150400.3.26.1 | SUSE-SU-2024:1113-1 |
| SUSE Enterprise Storage 7.1 | squid | 4.17-150000.5.52.1 | SUSE-SU-2024:1114-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | squid | 6.8-1.1 | openSUSE-SU-2024:13757-1 |
| openSUSE Leap 15.5 | squid | 5.7-150400.3.26.1 | SUSE-SU-2024:1113-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | squid | 7:6.6-1.amzn2023.0.3 | ALAS2023-2024-578 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | squid | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | squid | 7:5.5-6.0.1.el9_3.8 | ELSA-2024-1376 |
| Oracle Linux 8 | libecap +1 | 1.0.1-2.module+el8.9.0+90083+f7556140 | ELSA-2024-1375 |
| Oracle Linux 8 | squid | 7:4.15-7.module+el8.9.0+90184+ff65e696.10 | ELSA-2024-1375 |
Advisories 21
- ALSA-2024:1376 Important: squid security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2024:1375 Important: squid:4 security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2024:2777 Red Hat Security Advisory: squid:4 security update Red Hat Security Advisories (RHSA) · Sep 9, 2026
- RHSA-2024:2822 Red Hat Security Advisory: squid:4 security update Red Hat Security Advisories (RHSA) · Sep 9, 2026
- RHSA-2024:1833 Red Hat Security Advisory: squid security update Red Hat Security Advisories (RHSA) · Sep 9, 2026
- RHSA-2024:1832 Red Hat Security Advisory: squid:4 security update Red Hat Security Advisories (RHSA) · Sep 9, 2026
- RHSA-2024:1515 Red Hat Security Advisory: squid security and bug fix update Red Hat Security Advisories (RHSA) · Sep 9, 2026
- RHSA-2024:1479 Red Hat Security Advisory: squid:4 security update Red Hat Security Advisories (RHSA) · Sep 9, 2026
- RHSA-2024:1375 Red Hat Security Advisory: squid:4 security update Red Hat Security Advisories (RHSA) · Sep 9, 2026
- RHSA-2024:1376 Red Hat Security Advisory: squid security update Red Hat Security Advisories (RHSA) · Sep 9, 2026
- USN-6728-1 squid vulnerabilities Ubuntu Security Notices (USN) · Apr 27, 2026
- WID-SEC-2024-0544 Squid: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Apr 19, 2026
- DLA-4083-1 squid - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:13757-1 squid-6.8-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:1114-1 Security update for squid SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:1115-1 Security update for squid SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:1113-1 Security update for squid SUSE / openSUSE Security Updates · Feb 4, 2026
- ALAS2023-2024-578 Important: squid security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 26, 2025
- RLSA-2024:1375 Important: squid:4 security update Rocky Linux Security Advisories · May 7, 2025
- ELSA-2024-1375 Important: squid:4 security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Mar 21, 2024
- ELSA-2024-1376 Important: squid security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Mar 20, 2024
References
- https://github.com/squid-cache/squid/security/advisories/GHSA-72c2-c3wm-8qxc
- http://www.squid-cache.org/Versions/v6/SQUID-2024_1.patch
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7R4KPSO3MQT3KAOZV7LC2GG3CYMCGK7H/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XWQHRDRHDM5PQTU6BHH4C5KGL37X6TVI/
- https://security.netapp.com/advisory/ntap-20240605-0001/