CVE-2018-21246
highpriority · track · 40EPSS 0.027 · 86 %ileEUUSEPSS · scored 2026-10-28
Caddy before 0.10.13 mishandles TLS client authentication, as demonstrated by an authentication bypass caused by the lack of the StrictHostMatching mode.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-gr7w-x2jp-3xgwCaddy vulnerable to Authentication Bypass due to mishandling of TLS client authentication2022-10-06ghsa · osvUS
Caddy before 0.10.13 mishandles TLS client authentication, as demonstrated by an authentication bypass caused by the lack of the StrictHostMatching mode.
- GO-2020-0043Authentication bypass in github.com/mholt/caddy2021-04-14vendor · osvUS
Due to improper TLS verification when serving traffic for multiple SNIs, an attacker may bypass TLS client authentication by indicating an SNI during the TLS handshake that is different from the name in the HTTP Host header.
also known as (5)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- https://bugs.gentoo.org/715214cnnvd
- https://github.com/caddyserver/caddy/releases/tag/v0.10.13cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2018-21246cnnvd
- https://bugs.gentoo.org/715214enisa_euvd
- https://github.com/caddyserver/caddy/releases/tag/v0.10.13enisa_euvd
- https://bugs.gentoo.org/715214Third Party Advisorynvd
- https://github.com/caddyserver/caddy/releases/tag/v0.10.13Release NotesThird Party Advisorynvd
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