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FKIE_CVE-2026-77281

Vulnerability from fkie_nvd - Published: 2026-09-17 21:17 - Updated: 2026-09-17 21:17
Severity
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
Summary
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
security-advisories@github.comhttps://github.com/caddyserver/caddy/commit/176b043b0104cee3f894023cd5a598ac29e404bb
security-advisories@github.comhttps://github.com/caddyserver/caddy/pull/7761
security-advisories@github.comhttps://github.com/caddyserver/caddy/releases/tag/v2.11.4
security-advisories@github.comhttps://github.com/caddyserver/caddy/security/advisories/GHSA-j8px-rmrx-76h9
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "caddy",
          "vendor": "caddyserver",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.11.4"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "id": "CVE-2026-77281",
  "lastModified": "2026-09-17T21:17:37.890",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.5,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-09-17T21:17:37.890",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/caddyserver/caddy/commit/176b043b0104cee3f894023cd5a598ac29e404bb"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/caddyserver/caddy/pull/7761"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/caddyserver/caddy/releases/tag/v2.11.4"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/caddyserver/caddy/security/advisories/GHSA-j8px-rmrx-76h9"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-94"
        },
        {
          "lang": "en",
          "value": "CWE-178"
        },
        {
          "lang": "en",
          "value": "CWE-770"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}



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