CVE-2026-73051
MediumCVSS 6.3Summary
actix-http versions before 3.12.1 contain an HTTP request smuggling vulnerability in the HTTP/1.1 parser that accepts requests with both Content-Length and Transfer-Encoding: chunked headers. Unauthenticated remote attackers can exploit this through a front-end intermediary to desynchronize backend requests and smuggle malicious HTTP requests to the Actix service.
Risk Assessment
Attackers can bypass access controls, poison caches, or perform other attacks on the backend, potentially leading to data integrity and confidentiality breaches.
Recommendation
Update actix-http to version 3.12.1 or later. Also configure the front-end to reject requests with both headers.
Original NVD description (English source)
actix-http versions before 3.12.1 contain an HTTP request smuggling vulnerability in the HTTP/1.1 parser that accepts requests with both Content-Length and Transfer-Encoding: chunked headers. Unauthenticated remote attackers can exploit this through a front-end intermediary to desynchronize backend requests and smuggle malicious HTTP requests to the Actix service.