Buffer overflow in Cloudflare Octorpki
CVE-2021-3761
Any CA issuer in the RPKI can trick OctoRPKI prior to 1.3.0 into emitting an invalid VRP "MaxLength" value, causing RTR sessions to terminate. An attacker can use this to disable RPKI Origin Validation in a victim network (for example AS 13335 - Cloudflare) prior to launching a BGP hijack which during normal operations would be rejected as "RPKI invalid". Additionally, in certain deployments RTR session flapping in and of itself also could cause BGP routing churn, causing availability issues.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.012 (67.4th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 67th percentile — 67.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: 0.000
Affected products
- Cloudflare Octorpki — versions unspecified
- Debian Linux — versions 11.0
Weakness classification (CWE)
References
- github.com/cloudflare/cfrpki/security/advisories/GHSA-c8xp-8mf3-62h9 (Patch, Third Party Advisory)
- www.debian.org/security/2022/dsa-5041 (vendor-advisory, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-3761?
- CVE-2021-3761 is a high-severity vulnerability in Cloudflare Octorpki, classified under Out-of-bounds Write. CVSS score: 7.5/10. Published 2021-09-09.
- How severe is CVE-2021-3761?
- High severity. CVSS v3 base score is 7.5 out of 10.