CVE-2022-42917
FRRouting Privilege Escalation via TOCTOU Race Condition
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.
INFO
Published Date :
Sept. 14, 2026, 12:16 a.m.
Last Modified :
Sept. 14, 2026, 12:16 a.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2022-42917
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update FRRouting FRR to version 8.5 or later.
- Monitor configuration directory permissions.
- Ensure proper ownership of config files.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2022-42917.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2022-42917 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2022-42917
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2022-42917 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2022-42917 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Sep. 14, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H Added CWE CWE-367 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2022/42xxx/CVE-2022-42917.json">CVE-2022-42917</a> Added Reference https://bugzilla.suse.com/show_bug.cgi?id=1204124 Added Reference https://frrouting.org/security/cve-2022-42917/ Added Reference https://github.com/FRRouting/frr/commit/972cdc560e339d70c0ee5fb70ec636ab78f00bca Added Reference https://github.com/FRRouting/frr/compare/frr-8.4...frr-8.5