CVE-2022-42917

Publication date 14 September 2026

Last updated 15 October 2026

Ubuntu priority

Cvss 3 Severity Score

Description

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.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
frr	26.10 stonking	Not affected
	26.04 LTS resolute	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Vulnerable
	20.04 LTS focal	Needs evaluation
quagga	26.10 stonking	Not in release
	26.04 LTS resolute	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release
	20.04 LTS focal	Needs evaluation
	18.04 LTS bionic	Needs evaluation
	16.04 LTS xenial	Needs evaluation

Notes

sbeattie

the quagga project was renamed to frr

mdeslaur

This was fixed all the way back in frr 8.4.1-1

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
frr	Upstream: 972cdc5

Severity score breakdown

CVSS version: CVSS v3.0

Base score 6.7 · Medium

Base metrics

Parameter	Value
Attack vector	Local
Attack complexity	High
Privileges required	Low
User interaction	Required
Scope	Unchanged
Confidentiality impact	High
Integrity impact	High
Availability impact	High

Scores

Parameter	Value
Base score	6.7 · Medium
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H