CVE-2026-77281
Caddy: rewrite placeholder re-expansion
MEDIUM 6.5EPSS 0.5%
Caddy is an extensible server platform that uses TLS by default. In version 2.11.3 and earlier, three configuration-dependent weaknesses affect the handler and placeholder layer. In modules/caddyhttp/rewrite/rewrite.go, Rewrite.Rewrite() can pass attacker-controlled replacement bytes through buildQueryString for a second placeholder expansion when a rewrite URI ends with a literal question mark, allowing injected environment or request-variable placeholders to disclose data and, when the file provider is registered, allowing injected file placeholders to disclose readable files. The issue is fixed in version 2.11.4.
- Affected
- caddyserver · caddy
- CVSS v3.1 GITHUB
- 6.5 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - EPSS
- 0.49% chance of exploitation in the next 30 days, 41st percentile
- Published
- 2026-09-17
- Updated
- 2026-09-18