CVE-2026-66746 (GCVE-0-2026-66746)
Vulnerability from cvelistv5 – Published: 2026-07-28 16:06 – Updated: 2026-07-29 13:50 X_Open Source
VLAI
EPSS
VEX
Title
Rouille 0.4.0 - 3.6.2 HTTP Response Splitting via Header Injection
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.
Severity
5.4 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-29 13:50 UTC
CWE
- CWE-113 - Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/theopaid/HTTP-Response-Splitti… | technical-descriptionexploit |
| https://www.vulncheck.com/advisories/rouille-http… | third-party-advisory |
Impacted products
Date Public
2026-07-26 00:00
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