CVE-2022-3996 — If an X

If an X.509 certificate contains a malformed policy constraint and policy processing is enabled, then a write lock will be taken twice recursively. On some operating systems (most widely: Windows) this results in a denial of service when the affected process hangs. Policy process

01What is this vulnerability?

If an X.509 certificate contains a malformed policy constraint and policy processing is enabled, then a write lock will be taken twice recursively. On some operating systems (most widely: Windows) this results in a denial of service when the affected process hangs. Policy processing being enabled on a publicly facing server is not considered to be a common setup.

02Affected products

Vendor	Product	Versions
OpenSSL	OpenSSL	3.0.0

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: 2022-12-13T15:43:06.821Z
• Last modified: 2024-08-03T01:27:54.475Z

09References

• www.openssl.org — https://www.openssl.org/news/secadv/20221213.txt
• github.com — https://github.com/openssl/openssl/commit/7725e7bfe6f2ce8146b6552b44e0d226be7638…