CVE-2026-76925

CVE-2026-76925

A flaw was found in Flatpak. A Time-of-check to time-of-use (TOCTOU) race condition exists in the `org.freedesktop.Flatpak.SystemHelper` component. This vulnerability occurs because a privileged `chmod` operation executes before the OSTree repository validation within the `Deploy()` function. An attacker can exploit this timing window to redirect symlinks to arbitrary files, potentially leading to unauthorized file manipulation or information disclosure.

Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)

CVSS v3 metric

CVSS v3 base score 5.8 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L.

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-76925?
CVE-2026-76925 is a medium-severity vulnerability, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 5.8/10. Published 2026-09-04.
How severe is CVE-2026-76925?
Medium severity. CVSS v3 base score is 5.8 out of 10.