CVE-2026-45135

Caddy is an extensible server platform that uses TLS by default. From 2.7.0 until 2.11.3, the FastCGI transport's splitPos() in modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go misuses golang.org/x/text/search with search.IgnoreCase when the request path contains a non-ASCII byte. Two distinct flaws in that fallback let an attacker mislead Caddy's FastCGI splitting into treating a non-.php (or other configured split_path extension) file as a script. In any deployment where the attacker can place content into a file served via FastCGI (uploads, file storage, etc.), this can be escalated to remote code execution by crafting a URL whose path triggers either flaw. This vulnerability is fixed in 2.11.3.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/caddyserver/caddy/security/advisories/GHSA-m675-2p33-xv9g	Exploit Vendor Advisory
https://github.com/caddyserver/caddy/security/advisories/GHSA-m675-2p33-xv9g	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:caddyserver:caddy:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-23 18:17

Updated : 2026-06-26 18:04

NVD link : CVE-2026-45135

Mitre link : CVE-2026-45135

CVE.ORG link : CVE-2026-45135

JSON object : View

Products Affected

caddyserver

caddy

CWE

CWE-20

Improper Input Validation

CWE-176

Improper Handling of Unicode Encoding

CWE-178

Improper Handling of Case Sensitivity

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