Vulnerability in OpenBSD LibreSSL

[ Description ]Official description

LibreSSL ocspcheck through 4.4.0 contains a cleartext transmission vulnerability because url2host() discards the OCSP URL scheme and http_alloc() only selects TLS for port 443. On-path network attackers can read OCSP requests sent to https responder URLs on non-443 ports, exposing certificate serial numbers, issuer hashes, and nonces.

[ 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/commit/0f7039667044d1cd252cc72134e499186da4da25
• www.vulncheck.com/advisories/libressl-ocspcheck-through-4.4.0-cleartext-transmission-of…