CVE-2026-73051: actix-http · HTTP Request/Response Smuggling
Affects actix-httpSource CVE Database V5
Not known to be exploited · CVSS 6.3 Medium : upgrade to 3.12.1 when convenient.
Data as of 12 Nov 2026, 23:24 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 6.3 |
|---|
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 47% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.12.1
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 14 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Upgrade actix-http and actix/actix-http to 3.12.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| actixactix-http | Affected
| Fixed in
|
crates.ioactix/actix-httppkg:cargo/actix/actix-httpOther threats | Affected
| Fixed in
|
crates.ioactix-httppkg:cargo/actix-httpOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available in actix-http version 3.12.1 and later. Users should upgrade to version 3.12.1 or newer to remediate this vulnerability. Patch status is inferred from the affected versions and the version where the vulnerability is fixed; no official vendor advisory was provided in the input. Until upgraded, users should consider mitigating exposure by restricting or validating HTTP headers at front-end intermediaries if possible.
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.