Description
Libreswan 4.9 allows remote attackers to cause a denial of service (assert failure and daemon restart) via crafted TS payload with an incorrect selector length.
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 13 | libreswan | 4.9-2 | — |
| Debian 12 | libreswan | 4.9-2 | — |
| Debian 11 | libreswan | 4.3-1+deb11u3 | DSA-5368-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | libreswan | No fix yet | — |
| Ubuntu 26.04 LTS | libreswan | No fix yet | — |
| Ubuntu 25.10 | libreswan | No fix yet | — |
| Ubuntu 24.04 LTS | libreswan | No fix yet | — |
| Ubuntu 22.04 LTS | libreswan | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | libreswan | No fix yet | — |
| Ubuntu 18.04 LTS | libreswan | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | libreswan | 4.9-2.el9_2 | RHSA-2023:2633 |
| RHEL 8 | libreswan | 4.9-2.el8_8.2 | RHSA-2023:3095 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9.0 E4S | libreswan | 4.6-3.el9_0.3 | RHSA-2024:10594 |
| Red Hat OpenShift 4 | libreswan | 4.6-3.el9_0.3 | RHBA-2024:11565, RHBA-2024:11525, RHBA-2024:11505 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 9 | libreswan | 4.9-2.el9_2 | ALSA-2023:2633 |
| AlmaLinux 8 | libreswan | 4.9-2.el8_8.2 | ALSA-2023:3095 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.17 | libreswan | 4.9-r1 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | libreswan | 4.9-2.0.1.el9_2 | ELSA-2023-2633 |
| Oracle Linux 8 | libreswan | 4.9-2.0.1.el8_8.2 | ELSA-2023-3095 |
Advisories 12
- ALSA-2023:2633 Moderate: libreswan security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2023:3095 Moderate: libreswan security and bug fix update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2024:10594 Red Hat Security Advisory: libreswan security update Red Hat Security Advisories (RHSA) · Aug 26, 2026
- WID-SEC-2023-1185 Red Hat Enterprise Linux: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 3, 2026
- DSA-5368-1 libreswan - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RHBA-2024:11505 Red Hat Bug Fix Advisory: OpenShift Container Platform 4.16.28 packages and security update Red Hat Security Advisories (RHSA) · Jan 29, 2026
- RHBA-2024:11565 Red Hat Bug Fix Advisory: OpenShift Container Platform 4.15.42 packages update Red Hat Security Advisories (RHSA) · Jan 29, 2026
- RHBA-2024:11525 Red Hat Bug Fix Advisory: OpenShift Container Platform 4.17.10 packages and security update Red Hat Security Advisories (RHSA) · Jan 29, 2026
- RHSA-2023:3095 Red Hat Security Advisory: libreswan security and bug fix update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- RHSA-2023:2633 Red Hat Security Advisory: libreswan security update Red Hat Security Advisories (RHSA) · Nov 22, 2025
- ELSA-2023-3095 Moderate: libreswan security and bug fix update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 24, 2023
- ELSA-2023-2633 Moderate: libreswan security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · May 17, 2023
References
- https://github.com/libreswan/libreswan/issues/954
- DSA-5368 vendor-advisory
- FEDORA-2023-a2348480cb vendor-advisory
- FEDORA-2023-42ec148952 vendor-advisory