CVE-2026-119559 json
OpenLiteSpeed through 1.9.4 mTLS Bypass via HTTP/3 SNI and Host Mismatch
published 10d ago modified 4d ago also EUVD-2026-113824
- cvss
- 5.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
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.
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4d ago
Exploit prediction
0.29% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- abraxaslabs.tech https://abraxaslabs.tech/research/openlitespeed-h3-mtls-verifycontext referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.2 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N |
| CNA | 4.0 | 8.2 | CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- litespeedtech openlitespeed
Classification
- Weakness
-
- CWE-295 Improper Certificate Validation
References
-
abraxaslabs.tech
/research/openlitespeed-h3-mtls-verifycontext
third-party-advisory, exploit
-
github.com
/litespeedtech/openlitespeed/blob/v1.9.4/src/http/httpsession.cpp#L1665-L1672
technical-description
-
github.com
/litespeedtech/openlitespeed/blob/v1.9.4/src/sslpp/hiocrypto.h#L49-L50
technical-description
-
github.com
/litespeedtech/openlitespeed/blob/v1.9.4/src/quic/quicstream.h#L33-L37
technical-description
-
github.com
/litespeedtech/openlitespeed
product
-
vulncheck.com
/advisories/openlitespeed-through-1.9.4-mtls-bypass-via-http-3-sni-and-host-mismatch
third-party-advisory
Sources
- CVE List CVE-2026-119559
- NVD CVE-2026-119559
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.