CVE-2026-118371

Description

LibreSSL through 4.4.0 contains a CRLF injection vulnerability in the libcrypto OCSP_sendreq_new() and OCSP_parse_url() functions, which write unvalidated request paths into the OCSP POST request line. Attackers can embed carriage return and line feed characters in a certificate's Authority Information Access OCSP URI to inject HTTP headers or split requests sent to responders and proxies.

References

• https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-4.4.0-relnotes.txt
• https://github.com/libressl/portable
• https://github.com/openbsd/src/blob/3903c41d301d66facec69f7bf776b182cbc5ed62/lib/libcrypto/ocsp/ocsp_ht.c#L184
• https://github.com/openbsd/src/commit/d3f7195f4849d8a699cea4a3a67677f4b3dc1591
• https://www.vulncheck.com/advisories/libressl-through-4.4.0-crlf-injection-via-ocsp-sendreq-new-request-line