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.
CVSS Details
- CVSS 3.1 Base Score: 4.2
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | — | Upgrade caddy | Aug 11, 2026 | Aug 11, 2026 |
| Freebsd | — | Upgrade caddy | Jun 15, 2026 | Jun 13, 2026 |
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