CVE-2026-4878: 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…

PriorityP338high7CVSS 3.1

AVLACHPRLUINSUCHIHAH

EPSS

0.19%

8.6th percentile

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.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
debian	libcap2	< libcap2 1:2.78-1 (forky)	libcap2 1:2.78-1 (forky)
redhat	enterprise_linux	—	—
redhat	enterprise_linux	—	—
redhat	enterprise_linux	—	—
redhat	openshift_container_platform	—	—
ubuntu	libcap2	—	—

CVSS provenance

nvdv3.17.0HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

osv6.7MEDIUM

vendor_debian6.7MEDIUM

vendor_redhat6.7MEDIUM

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