CVE-2026-66754: tomaka rouille Reachable Assertion

Vulnerability summary

CVE-2026-66754 is a high (CVSS 8.2) Reachable Assertion vulnerability in tomaka rouille. EPSS estimates a 0.56% chance of exploitation in the next 30 days, higher than 46.1% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 28-07-2026
   PublishedVulnerability first disclosed.
2. 29-07-2026
   Last modifiedVulnerability information updated.

Description

Rouille 0.1.6 through 3.6.2 contains a reachable assertion vulnerability in the Request::remove_prefix function that allows remote unauthenticated attackers to crash the server by sending a crafted percent-encoded URL. Attackers can send a request whose decoded path matches a configured prefix while the raw percent-encoded path does not, causing the assert! to fail and triggering either a 500 error or full process termination depending on the panic configuration.

• CWE-617Reachable AssertionThe product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.