Vulnerability Description
OpenLiteSpeed through 1.9.4 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to evade virtual host client certificate requirements over HTTP/3. Because QuicStream inherits a verifyContext() implementation that always returns true, attackers can present a non-mTLS host's SNI with a protected Host header to access protected content.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://abraxaslabs.tech/research/openlitespeed-h3-mtls-verifycontext
- https://github.com/litespeedtech/openlitespeed
- https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/http/httpsession.
- https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/quic/quicstream.h
- https://github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/sslpp/hiocrypto.h
- https://www.vulncheck.com/advisories/openlitespeed-through-1.9.4-mtls-bypass-via
FAQ
What is CVE-2026-119559?
CVE-2026-119559 is a vulnerability with a CVSS score of 5.9 (MEDIUM). OpenLiteSpeed through 1.9.4 contains an authentication bypass vulnerability that allows unauthenticated remote attackers to evade virtual host client certificate requirements over HTTP/3. Because Quic...
How severe is CVE-2026-119559?
CVE-2026-119559 has been rated MEDIUM with a CVSS base score of 5.9/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-119559?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.