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
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
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
5.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
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
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7156 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
tomaka rouille Affected: 0.4.0 , ≤ 3.6.2 (semver)
guessed Create a notification for this product.
Date Public
2026-07-26 00:00
Credits
Theodosis Paidakis
Show details on NVD website
To clipboard 

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