Vulnerability in Frrouting

CVE-2022-42917

In FRRouting FRR before 8.5, the service user (usually frr) can escalate its privileges to root by monitoring the configuration directory (/etc/frr) and replacing config files upon creation with, for example, symlinks to change the ownership of arbitrary files. This is a TOCTOU Race Condition caused by a combination of touch and chown.

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

Published · last modified .

CVSS v3 metric

CVSS v3 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.

EPSS exploit prediction

EPSS: 0.001 (1.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 1.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2022-42917: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: -0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2022-42917?
CVE-2022-42917 is a medium-severity vulnerability in Frrouting, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 6.7/10. Published 2026-09-14.
How severe is CVE-2022-42917?
Medium severity. CVSS v3 base score is 6.7 out of 10.