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
Source GCVE Database
Not known to be exploited · CVSS 8.2 High.
Data as of 30 Oct 2026, 13:35 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 8.2 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 5.9 |
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 30 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| litespeedtechopenlitespeed | Affected
| Fixed in– |
GitHubopenlitespeedpkg:github/openlitespeedOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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.
References
- nvd.nist.gov/vuln/detail/CVE-2026-119559 (opens in a new tab)
- abraxaslabs.tech/research/openlitespeed-h3-mtls-verifycontext (opens in a new tab)
- github.com/litespeedtech/openlitespeed (opens in a new tab)
- github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/http/httpsession.cpp (opens in a new tab)
- github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/quic/quicstream.h (opens in a new tab)
- github.com/litespeedtech/openlitespeed/blob/v1.9.4/src/sslpp/hiocrypto.h (opens in a new tab)
- vulncheck.com/advisories/openlitespeed-through-1.9.4-mtls-bypass-via-http-3-sni-and-host-mismatch (opens in a new tab)