Executive brief
A security flaw in Erlang's core networking libraries could allow attackers to bypass certificate revocation checks. This affects applications using SSL/TLS with OCSP stapling, potentially allowing a user to connect to a malicious or compromised server that is using a revoked security certificate. This could lead to the interception of sensitive data or unauthorized access to communications.
Technical details
The OCSP response validation in Erlang's 'public_key:pkix_ocsp_validate/5' function fails to verify that a CA-designated responder certificate was cryptographically signed by the issuing CA. The implementation only checks for a matching issuer name and the 'OCSPSigning' extended key usage (EKU). An attacker capable of intercepting or controlling OCSP responses can provide a self-signed certificate with matching metadata to forge responses, effectively marking revoked certificates as valid. This affects SSL/TLS clients using OCSP stapling and applications directly calling the affected API. Patches are available in OTP versions 28.4.2 and 27.3.4.10.
Affected products
- Erlang OTP 27.0 to 28.4.2, 27.3.4.10
- Erlang public_key 1.16 to 1.20.3, 1.17.1.2
- Erlang ssl 11.2 to 11.5.4, 11.2.12.7
Timeline
- 2026-04-07: advisory: Initial publication of CVE-2026-32144
- 2026-04-07: disclosed
References
- https://github.com/
- https://cna.erlef.org/cves/CVE-2026-32144.html
- https://github.com/erlang/otp/commit/49033a6d93a5be0ee0dce04e1fb8b4ae7de1e0c0
- https://github.com/erlang/otp/commit/ac7ff528be857c5d35eb29c7f24106e3a16d4891
- https://github.com/erlang/otp/security/advisories/GHSA-gxrm-pf64-99xm
- https://www.erlang.org/doc/system/versions.html