Description
The PAM module pam_cap.so of libcap configuration supports group names starting with “@”, during actual parsing, configurations not starting with “@” are incorrectly recognized as group names. This may result in nonintended users being granted an inherited capability set, potentially leading to security risks. Attackers can exploit this vulnerability to achieve local privilege escalation on systems where /etc/security/capability.conf is used to configure user inherited privileges by constructing specific usernames.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| OpenAnolis | Anolis OS | 2.73;0 | — |
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 | libcap2 | 1:2.73-4 | — |
| Debian 13 | libcap2 | 1:2.73-4 | — |
| Debian 12 | libcap2 | 1:2.66-4+deb12u1 | — |
| Debian 11 | libcap2 | 1:2.44-1+deb11u1 | DLA-4092-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | libcap2 | 1:2.66-5ubuntu2.2 | USN-7287-1 |
| Ubuntu 22.04 LTS | libcap2 | 1:2.44-1ubuntu0.22.04.2 | USN-7287-1 |
| Ubuntu 20.04 LTS | libcap2 | 1:2.32-1ubuntu0.2 | USN-7287-1 |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | libcap2 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | libcap2 | No fix yet | — |
| Ubuntu Pro 14.04 LTS | libcap2 | No fix yet | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | libcap +2 | 2.48-2.amzn2023.0.4 | ALAS2023-2025-897 |
| Amazon Linux 2 | libcap +2 | 2.54-1.amzn2.0.3 | ALAS2-2025-2796 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | libcap | 2.69-2 | — |
| Azure Linux 2 (CBL-Mariner) | libcap | 2.60-3 | — |
Advisories 9
- SSA-398330 SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5 Siemens ProductCERT · Oct 13, 2026
- USN-7287-1 libcap2 vulnerability Ubuntu Security Notices (USN) · Apr 27, 2026
- DLA-4092-1 libcap2 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- ICSA-26-043-06 Siemens SINEC OS CISA ICS & IT advisories · Feb 25, 2026
- SSA-089022 SSA-089022: Multiple Vulnerabilities in Third-Party Components in SINEC OS before V3.3 Siemens ProductCERT · Feb 24, 2026
- NCSC-2025-0246 Kwetsbaarheden verholpen in Siemens producten NCSC-NL (Netherlands) · Aug 12, 2025
- ICSA-23-348-10 Siemens SIMATIC S7-1500 CISA ICS & IT advisories · Aug 12, 2025
- ALAS2023-2025-897 Important: libcap security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Mar 26, 2025
- ALAS2-2025-2796 Important: libcap security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Mar 25, 2025