Description
Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to an Out-of-bounds Write error when assigning ESI variables, Squid is susceptible to a Memory Corruption error. This error can lead to a Denial of Service attack.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| squid-cache | squid | >= 3.0, <= 3.5.28, >= 4.0, <= 4.16, >= 5.0, <= 5.9, >= 6.0, <= 6.9 | — |
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 | 6.10-1 | — |
| Debian 13 | squid | 6.10-1 | — |
| Debian 12 | squid | 5.7-2+deb12u2 | DSA-5751-1 |
| Debian 11 | squid | 4.13-10+deb11u4 | DLA-4083-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | squid | 6.6-1ubuntu5.1 | USN-6907-1 |
| Ubuntu 22.04 LTS | squid | 5.9-0ubuntu0.22.04.2 | USN-6907-1 |
| Ubuntu 20.04 LTS | squid | 4.10-1ubuntu1.13 | USN-6907-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | squid3 | 3.5.27-1ubuntu1.14+esm3 | USN-6907-1 |
| Ubuntu Pro 16.04 LTS | squid3 | 3.5.12-1ubuntu7.16+esm4 | USN-6907-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | squid | 7:5.5-13.el9_4 | RHSA-2024:4861 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.2 EUS | squid | 7:5.5-5.el9_2.7 | RHSA-2024:5906 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 9 | squid | 7:5.5-13.el9_4 | ALSA-2024:4861 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 9 | squid | 7:5.5-13.el9_4 | RLSA-2024:4861 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP6 | squid | 6.10-150600.3.6.1 | SUSE-SU-2024:2268-1 |
| SLES 15 SP5 | squid | 5.7-150400.3.32.1 | SUSE-SU-2024:2269-1 |
| SLES 15 SP3 | squid | 4.17-150000.5.55.1 | SUSE-SU-2025:03521-1 |
| SLES 12 SP5 | squid | 4.17-4.50.1 | SUSE-SU-2024:2270-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP3 | squid | 4.17-150000.5.55.1 | SUSE-SU-2025:03521-1 |
| SLES for SAP 12 SP5 | squid | 4.17-4.50.1 | SUSE-SU-2024:2270-1 |
| SLE HPC 15 SP3 | squid | 4.17-150000.5.55.1 | SUSE-SU-2025:03521-1 |
| SUSE Enterprise Storage 7.1 | squid | 4.17-150000.5.55.1 | SUSE-SU-2025:03521-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | squid | 6.10-1.1 | openSUSE-SU-2024:14080-1 |
| openSUSE Leap 15.6 | squid | 6.10-150600.3.6.1 | SUSE-SU-2024:2268-1 |
| openSUSE Leap 15.5 | squid | 5.7-150400.3.32.1 | SUSE-SU-2024:2269-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | squid | 7:6.6-1.amzn2023.0.4 | ALAS2023-2024-687 |
| Amazon Linux 2 | squid +2 | 7:3.5.20-17.amzn2.7.21 | ALAS2-2024-2609 |
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 | 7:5.5-13.el9_4 | ELSA-2024-4861 |
Advisories 17
- ALSA-2024:4861 Moderate: squid security update AlmaLinux Security Advisories · Oct 29, 2026
- USN-6907-1 squid, squid3 vulnerability Ubuntu Security Notices (USN) · Jun 25, 2026
- RHSA-2024:4861 Red Hat Security Advisory: squid security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- RHSA-2024:5906 Red Hat Security Advisory: squid security update Red Hat Security Advisories (RHSA) · Mar 18, 2026
- DSA-5751-1 squid - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-4083-1 squid - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2024:4861 Moderate: squid security update Rocky Linux Security Advisories · Feb 5, 2026
- SUSE-SU-2024:2268-1 Security update for squid SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:2269-1 Security update for squid SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:2270-1 Security update for squid SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:14080-1 squid-6.10-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2025:03521-1 Security update for squid SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2025-1850 Xerox FreeFlow Print Server: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff BSI CERT-Bund (WID) · Nov 17, 2025
- WID-SEC-2024-1447 Squid: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Oct 9, 2025
- ALAS2-2024-2609 Moderate: squid security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Aug 13, 2024
- ALAS2023-2024-687 Moderate: squid security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Aug 6, 2024
- ELSA-2024-4861 Moderate: squid security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Jul 25, 2024