Vulnerability · Published May 13, 2026 · Assigned by GitHub_M
CVE-2026-44373Nitro: Proxy scope bypass via percent-encoded path traversal in `routeRules`
Medium 5.3
In plain English
A medium-severity path traversal in nitro from nitrojs. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 39% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)5.3Medium
Exploit odds (30 days)0.5%top 60.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
Nitro is a next generation server toolkit. Prior to 3.0.260429-beta, an attacker could bypass a proxy route rule by sending percent-encoded path traversal (..%2f) in the URL, causing Nitro to forward a request that the upstream resolved outside the configured scope. This vulnerability is fixed in 3.0.260429-beta.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | nitro | 3.0.260429-beta | GHSA-5w89-w975-hf9q |
| npm | nitropack | 2.13.4 | GHSA-5w89-w975-hf9q |
Affected products (as reported)
Weakness: CWE-22 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
References
- https://github.com/nitrojs/nitro/security/advisories/GHSA-5w89-w975-hf9q x_refsource_CONFIRM
- https://github.com/nitrojs/nitro/pull/4222 x_refsource_MISC
- https://github.com/nitrojs/nitro/pull/4223 x_refsource_MISC
- https://github.com/nitrojs/nitro/releases/tag/v2.13.4 x_refsource_MISC
- https://github.com/nitrojs/nitro/releases/tag/v3.0.260429-beta x_refsource_MISC