---
id: CVE-2022-42917
title: >-
  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
  owner…
summary: >-
  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
  owner…
severity: medium
cvss: 6.7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-367
vendor: FRRouting
product: FRRouting
affected:
  - FRRouting < 4.5
published: '2026-09-14'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T19:56:19.073'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2022-42917'
references:
  - url: 'https://bugzilla.suse.com/show_bug.cgi?id=1204124'
    label: cve@mitre.org
  - url: 'https://frrouting.org/security/cve-2022-42917/'
    label: cve@mitre.org
  - url: >-
      https://github.com/FRRouting/frr/commit/972cdc560e339d70c0ee5fb70ec636ab78f00bca
    label: cve@mitre.org
  - url: 'https://github.com/FRRouting/frr/compare/frr-8.4...frr-8.5'
    label: cve@mitre.org
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2022/cve-2022-42917.json
  - url: 'https://access.redhat.com/security/cve/CVE-2022-42917'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532800'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2022-42917'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2022-42917'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.0013
epssPercentile: 0.02127
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-14T15:03:58.372990Z'
ingestedAt: '2026-09-14T15:23:07.468Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2022/cve-2022-42917.json)