CVE-2026-4878
Publication date 9 April 2026
Last updated 26 June 2026
Ubuntu priority
Description
A flaw was found in libcap. A local unprivileged user can exploit a Time-of-check-to-time-of-use (TOCTOU) race condition in the `cap_set_file()` function. This allows an attacker with write access to a parent directory to redirect file capability updates to an attacker-controlled file. By doing so, capabilities can be injected into or stripped from unintended executables, leading to privilege escalation.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libcap2 | 26.04 LTS resolute |
Not affected
|
| 25.10 questing |
Fixed 1:2.75-7ubuntu2.2
|
|
| 24.04 LTS noble |
Fixed 1:2.66-5ubuntu2.4
|
|
| 22.04 LTS jammy |
Fixed 1:2.44-1ubuntu0.22.04.3
|
|
| 20.04 LTS focal |
Fixed 1:2.32-1ubuntu0.2+esm1
|
|
| 18.04 LTS bionic |
Fixed 1:2.25-1.2ubuntu0.1~esm2
|
|
| 16.04 LTS xenial |
Fixed 1:2.24-12ubuntu0.1~esm2
|
|
| 14.04 LTS trusty |
Fixed 1:2.24-0ubuntu2+esm2
|
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CVSS version: CVSS v3.0
Base score
6.7 · Medium
Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
References
Related Ubuntu Security Notices (USN)
- USN-8193-2
- libcap vulnerability
- 23 June 2026