Quick answers
- Is CVE-2026-66754 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-66754 being exploited in the wild.
- How severe is CVE-2026-66754?
- High severity, with a CVSS score of 7.5, published 28 July 2026.
- Which products and versions are affected?
- Tomaka Rouille 0.1.6 through 3.6.2.
- Is there a fix for CVE-2026-66754?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-66754 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-66754?
- Check whether you run Tomaka Rouille at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A reachable assertion vulnerability (CWE-617) exists in the `Request::remove_prefix` function of the Rouille library. The function performs a check on the percent-decoded URL path but executes an `assert!` statement against the raw, encoded path. By sending a request where the decoded path matches a configured prefix but the raw path does not (e.g., by percent-encoding a character within the prefix), an attacker can trigger an assertion failure. Depending on the Rust panic configuration, this results in either a 500 Internal Server Error or immediate process termination (Denial of Service). This attack is reachable over the network without authentication.
Affected products
- tomaka rouille 0.1.6 through 3.6.2
Timeline
- 2026-07-28: advisory: NVD and VulnCheck published the advisory.