CVE-2022-40302 — An issue was discovered in bgpd in FRRouting (FRR) through 8

An issue was discovered in bgpd in FRRouting (FRR) through 8.4. By crafting a BGP OPEN message with an option of type 0xff (Extended Length from RFC 9072), attackers may cause a denial of service (assertion failure and daemon restart, or out-of-bounds read). This is possible beca

01What is this vulnerability?

An issue was discovered in bgpd in FRRouting (FRR) through 8.4. By crafting a BGP OPEN message with an option of type 0xff (Extended Length from RFC 9072), attackers may cause a denial of service (assertion failure and daemon restart, or out-of-bounds read). This is possible because of inconsistent boundary checks that do not account for reading 3 bytes (instead of 2) in this 0xff case.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2023-05-03T00:00:00.000Z
• Last modified: 2025-01-30T16:06:39.072Z

09References

• github.com — https://github.com/FRRouting/frr/releases
• www.debian.org — https://www.debian.org/security/2023/dsa-5495
• lists.debian.org — https://lists.debian.org/debian-lts-announce/2023/09/msg00020.html