actix-http before 3.12.1 HTTP Request Smuggling via CL.TE (CVE-2026-73051) | HOL Guard CVE

Medium · CVSS 6.3CVE-2026-73051

actix-http before 3.12.1 HTTP Request Smuggling via CL.TE

Answer in brief

CVE-2026-73051 records a Medium severity (CVSS 6.3) vulnerability in actix-http before 3.12.1 HTTP Request Smuggling via CL.TE. The current sources do not mark it as known exploited. The current feed maps actix/actix-web (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 14, 2026Updated Aug 14, 2026Source checked Sep 29, 2026First seen by HOL Aug 14, 2026Material review Aug 14, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.3
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 6.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps actix/actix-web (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
actix/actix-webgeneric	>=0 <3.12.0	3.12.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for actix/actix-web.
Review the reported fix. Update actix/actix-web to 3.12.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 14, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 14, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 14, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.