CVE-2026-4878 MEDIUM

CVE-2026-4878: Libcap: libcap: privilege escalation via toctou race condition in cap_set_file()

Vendor Red Hat
Product Red Hat Enterprise Linux 6
Weakness CWE-367
Published April 9, 2026
Last update June 30, 2026

CVSS base score

6.7/10
Attack vector Local
Attack complexity High
Privileges required Low
User interaction Required
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

April 9, 2026 CVE published
June 30, 2026 Record updated