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TI-2026-47394 Aliases CVE-2026-66746GHSA-998j-f97v-vpgr

Rouille 0.4.0 - 3.6.2 HTTP Response Splitting via Header Injection

Priority MEDIUM 57CWE-113Published · Updated

Key facts

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

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

Summary

Rouille 0.4.0 through 3.6.2 contains an HTTP response splitting vulnerability that allows remote attackers to inject arbitrary response headers by embedding carriage return (0x0D) or line feed (0x0A) bytes into attacker-controlled input. Attackers can exploit percent-decoded query parameters reflected into response headers or inject bare LF characters into Cookie header values that are interpolated directly into Set-Cookie response headers, enabling cache poisoning, session fixation, and security header override attacks such as bypassing CSP or CORS policies.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0034 27th 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
tomakarouille0.4.0 – 3.6.2—No fix listedCNA
  • rouille Vendortomaka Affected 0.4.0 – 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-2026-66746
  2. 2026-10-03 Alias added: GHSA-998j-f97v-vpgr

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-2026-47508 Rouille 0.3.3 - 3.6.2 HTTP Request Smuggling via proxy Transfer-Encoding Header CVSS 4.0MEDIUM 6.3

Sources

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