CVE-2026-52846
Caddy: stripHTML template function bypass
- State
- Published
- Severity
- 4.2 Medium
- Published
- Jun 23, 2026
- Updated
- Jun 25, 2026
- Reserved
- Jun 8, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 4.2 Medium | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N | GitHub_M |
Weaknesses
- CWE-116 Improper Encoding or Escaping of Output
Affected Products
| Product | Versions |
|---|---|
caddycaddyserver |
|
References
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