Arbitrary Code Injection Affecting caddy package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-ECHOLATEST-CADDY-19964088
- published20 Sept 2026
- disclosed17 Sept 2026
Introduced: 17 Sep 2026
NewCVE-2026-77281 (opens in a new tab)How to fix?
There is no fixed version for Echo:latest caddy.
NVD Description
Note: Versions mentioned in the description apply only to the upstream caddy package and not the caddy package as distributed by Echo.
See How to fix? for Echo:latest relevant fixed versions and status.
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.
References
- https://advisory.echohq.com/cve/CVE-2026-77281
- https://github.com/caddyserver/caddy/commit/176b043b0104cee3f894023cd5a598ac29e404bb
- https://github.com/caddyserver/caddy/pull/7761
- https://github.com/caddyserver/caddy/releases/tag/v2.11.4
- https://github.com/caddyserver/caddy/security/advisories/GHSA-j8px-rmrx-76h9