CVE-2026-45135 (GCVE-0-2026-45135)

Vulnerability from cvelistv5 – Published: 2026-06-23 17:56 – Updated: 2026-06-23 18:30
VLAI
Title
Caddy: Unsafe Unicode Handling in FastCGI splitPos Allows Execution of Non-PHP Files
Summary
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.
Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-23 18:30 UTC
CWE
  • CWE-20 - Improper Input Validation
  • CWE-176 - Improper Handling of Unicode Encoding
  • CWE-178 - Improper Handling of Case Sensitivity
Assigner
References
Impacted products
Vendor Product Version CPE status
caddyserver caddy Affected: >= 2.7.0, < 2.11.3
guessed Create a notification for this product.
Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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