Description
Caddy is an extensible server platform that uses TLS by default. Prior to 2.11.4, Caddy’s stripHTML template function cannot reliably remove all HTML tags from input strings. Certain malformed HTML, such as <<>img src=x onerror=alert()>, can bypass the tag-stripping logic, potentially leaving dangerous content in the output if it is later rendered as HTML. This may allow client-side XSS in cases where untrusted strings are rendered unsafely. This vulnerability is fixed in 2.11.4.
References (1)
Core 1
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/caddyserver/caddy/security/advisories/GHSA-vcc4-2c75-vc9v
Scores
CVSS v3
4.2
EPSS
0.0017
EPSS Percentile
7.2%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
partial
Details
CWE
CWE-116
Status
published
Products (1)
caddyserver/caddy
< 2.11.4 (2 CPE variants)
Published
Jun 23, 2026
Tracked Since
Jun 24, 2026