Vulnerability in OpenBSD LibreSSL

[ Description ]Official description

LibreSSL ocspcheck through 4.4.0 contains a CRLF injection vulnerability that allows attackers to inject HTTP headers by embedding CR/LF sequences in a certificate's AIA OCSP URI path. Because url2host() copies the path without rejecting control characters and http_open() places it in the POST request line, attackers can inject headers or split OCSP requests sent to the responder host.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ Advisories ]Government CERT advisories

• BSI CERT-Bund27 Oct 2026WID-SEC-2026-4202

  LibreSSL: Multiple vulnerabilities Translated from German

  CVE-2026-118371CVE-2026-118374CVE-2026-118372+1 more CVEs

[ References ]References

• ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-4.4.0-relnotes.txt
• github.com/libressl/portable
• github.com/openbsd/src/blob/17a8e44328ee2505d69723a126a390a526e50370/usr.sbin/ocspcheck…
• github.com/openbsd/src/blob/17a8e44328ee2505d69723a126a390a526e50370/usr.sbin/ocspcheck…
• github.com/openbsd/src/commit/3adb7688a5bcfb675fa6d8b10e242022d620a23d
• github.com/openbsd/src/commit/6efdc4cce3fac9fa7208a9452f84de34c5a68e9f
• www.vulncheck.com/advisories/libressl-ocspcheck-through-4.4.0-crlf-injection-via-aia-oc…