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TI-2026-47508 Aliases CVE-2026-67181GHSA-fgf8-ph7p-m275

Rouille 0.3.3 - 3.6.2 HTTP Request Smuggling via proxy Transfer-Encoding Header

Priority MEDIUM 61CWE-444Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · Low · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Rouille 0.3.3 through 3.6.2 contains an HTTP request smuggling vulnerability that allows remote attackers to desynchronize HTTP message boundaries by exploiting improper header forwarding in the proxy implementation. The proxy in src/proxy.rs forwards the client's Transfer-Encoding header to upstream backends unchanged while transmitting a body already de-chunked by tiny_http, enabling CL.TE desynchronization attacks where attackers control where the backend believes the request body ends.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00414 35th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
tomakarouille0.3.3 – 3.6.2—No fix listedCNA
  • rouille Vendortomaka Affected 0.3.3 – 3.6.2 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-67181
  2. 2026-10-03 Alias added: GHSA-fgf8-ph7p-m275

References

Exploit 1

  • TI-2026-47402 Rouille 0.1.6 - 3.6.2 Reachable Assertion DoS via remove_prefix percent-encoding CVSS 4.0HIGH 8.2
  • TI-2026-47509 Rouille 0.3.3 - 3.6.2 HTTP Request Smuggling via proxy Header Injection CVSS 4.0MEDIUM 6.9
  • TI-2026-47394 Rouille 0.4.0 - 3.6.2 HTTP Response Splitting via Header Injection CVSS 4.0MEDIUM 5.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences