Red Hat Security Advisory: libcap security update
Libcap is a library for getting and setting POSIX.1e (formerly POSIX 6) draft 15 capabilities. Security Fix(es): * libcap: libcap: Privilege escalation via TOCTOU race condition in cap_set_file() (CVE-2026-4878) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
AI Analysis
Technical Summary
The vulnerability CVE-2026-4878 affects the libcap library in Red Hat Enterprise Linux 10 and 9. It is a TOCTOU race condition in the cap_set_file() function that allows a local unprivileged user with write access to a parent directory to redirect capability changes to an attacker-controlled file. This can result in injecting or stripping capabilities from unintended executables, enabling privilege escalation. Red Hat has issued security advisories RHSA-2026:12423 and RHSA-2026:12441 with updated libcap packages that fix this issue. The fix is available in libcap versions 2.69-7.el10_1.1 for RHEL 10 and 2.48-10.el9_7.1 for RHEL 9. The CVSS 3.1 vector is AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H, reflecting local attack vector, high attack complexity, low privileges required, user interaction needed, unchanged scope, and high impact on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation allows a local unprivileged user with write access to a parent directory to escalate privileges by modifying file capabilities on unintended executables. This can compromise system confidentiality, integrity, and availability. The vulnerability is rated medium severity with a CVSS score of 6.7. There are no known exploits in the wild currently.
Mitigation Recommendations
Red Hat has released official security updates fixing this vulnerability. Users should apply the updated libcap packages as described in Red Hat advisories RHSA-2026:12423 for RHEL 10 and RHSA-2026:12441 for RHEL 9. Detailed update instructions are available at https://access.redhat.com/articles/11258. Applying these updates fully mitigates the vulnerability. No additional action is required beyond patching.
Red Hat Security Advisory: libcap security update
Description
Libcap is a library for getting and setting POSIX.1e (formerly POSIX 6) draft 15 capabilities. Security Fix(es): * libcap: libcap: Privilege escalation via TOCTOU race condition in cap_set_file() (CVE-2026-4878) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
CVSS v3.1
Score 6.7medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-4878 affects the libcap library in Red Hat Enterprise Linux 10 and 9. It is a TOCTOU race condition in the cap_set_file() function that allows a local unprivileged user with write access to a parent directory to redirect capability changes to an attacker-controlled file. This can result in injecting or stripping capabilities from unintended executables, enabling privilege escalation. Red Hat has issued security advisories RHSA-2026:12423 and RHSA-2026:12441 with updated libcap packages that fix this issue. The fix is available in libcap versions 2.69-7.el10_1.1 for RHEL 10 and 2.48-10.el9_7.1 for RHEL 9. The CVSS 3.1 vector is AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H, reflecting local attack vector, high attack complexity, low privileges required, user interaction needed, unchanged scope, and high impact on confidentiality, integrity, and availability.
Potential Impact
Successful exploitation allows a local unprivileged user with write access to a parent directory to escalate privileges by modifying file capabilities on unintended executables. This can compromise system confidentiality, integrity, and availability. The vulnerability is rated medium severity with a CVSS score of 6.7. There are no known exploits in the wild currently.
Mitigation Recommendations
Red Hat has released official security updates fixing this vulnerability. Users should apply the updated libcap packages as described in Red Hat advisories RHSA-2026:12423 for RHEL 10 and RHSA-2026:12441 for RHEL 9. Detailed update instructions are available at https://access.redhat.com/articles/11258. Applying these updates fully mitigates the vulnerability. No additional action is required beyond patching.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:20595
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- 3.1
Threat ID: 6a16097de29bf47b50649db2
Added to database: 05/26/2026, 20:58:37 UTC
Last enriched: 07/26/2026, 00:34:09 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 112
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