Vulnerability in Tomaka Rouille

CVE-2026-67182

Rouille 0.3.3 through 3.6.2 contains an HTTP request smuggling vulnerability that allows remote attackers to bypass access controls by injecting bare line feed characters (0x0A) into client-supplied request header values that are copied verbatim to upstream connections without validation. Attackers can craft a header value containing a complete additional HTTP request that is interpreted as a separate request by backends such as Go net/http and Python http.server, causing the backend to process a smuggled request with attacker-chosen method, path, and headers that bypasses the rouille handler's access control logic.

Vulnerability class: HTTP Request Smuggling

EPSS: 0.004 (35.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:L.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-67182?
CVE-2026-67182 is a high-severity vulnerability in Tomaka Rouille, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 7.5/10. Published 2026-07-28.
How severe is CVE-2026-67182?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2026-67182 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.