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Fencer Intel
medium 5.8

CVE-2026-76925 json

Flatpak: flatpak: toctou race condition allows symlink redirection

published 2mo ago modified 6d ago also EUVD-2026-71774

cvss
5.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 0%
public exploits
0
none known

Summary

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.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-76925 updated cvss 5.8

flatpak: Flatpak: TOCTOU race condition allows symlink redirection

  • Red Hat Enterprise Linux 7 flatpak, flatpak-libs, flatpak-builder Red Hat Enterprise Linux 8 flatpak, flatpak-libs, flatpak-selinux, flatpak-session-helper Red Hat Enterprise Linux 9 flatpak, flatpak-libs, flatpak-selinux, flatpak-session-helper Red Hat Enterprise Linux 10 flatpak
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2mo ago

Exploit prediction

0.10% chance of exploitation in the next 30 days, higher than 0% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 3.1 5.8 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L

Affected products

  • Red Hat Red Hat Enterprise Linux 10
  • Red Hat Red Hat Enterprise Linux 7
  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 9

Classification

Weakness
  • CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.