CVE-2026-73051: actix-http has HTTP/1.1 CL.TE Request Smuggling

CVE-2026-73051 · Severity: medium · CVSS 4 · Published 2026-08-14

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.

Technologies: actix-http (crates.io). Vendors: crates.io.

Quick answers

Is CVE-2026-73051 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-73051 being exploited in the wild.
How severe is CVE-2026-73051?
Medium severity, with a CVSS score of 4, published 14 August 2026.
Which products and versions are affected?
actix-http (crates.io) SEMVER:introduced=0,fixed=3.12.1.
Is there a fix for CVE-2026-73051?
Yes. actix-http (crates.io): upgrade to 3.12.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-73051?
Check whether you run actix-http (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • actix-http (crates.io): upgrade to 3.12.1 or later
    cargo update -p actix-http

Affected products

  • actix-http (crates.io) SEMVER:introduced=0,fixed=3.12.1

Identifiers

  • CVE-2026-73051
  • GHSA-xhj4-vrgc-hr34

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.