{"id":"CVE-2026-33994","revision":"a83fa0e30abe4ef2b2f082e4e146cabf","records":[{"revision":"a83fa0e30abe4ef2b2f082e4e146cabf","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-33994","aliases":[],"title":"Locutus Prototype Pollution due to incomplete fix for CVE-2026-25521","description":"Locutus brings stdlibs of other programming languages to JavaScript for educational purposes. Starting in version 2.0.39 and prior to version 3.0.25, a prototype pollution vulnerability exists in the `parse_str` function of the npm package locutus. An attacker can pollute `Object.prototype` by overriding `RegExp.prototype.test` and then passing a crafted query string to `parse_str`, bypassing the prototype pollution guard. This vulnerability stems from an incomplete fix for CVE-2026-25521. The CVE-2026-25521 patch replaced the `String.prototype.includes()`-based guard with a `RegExp.prototype.test()`-based guard. However, `RegExp.prototype.test` is itself a writable prototype method that can be overridden, making the new guard bypassable in the same way as the original — trading one hijackable built-in for another. Version 3.0.25 contains an updated fix.","state":0,"publishedAt":"2026-03-27T22:15:47.131+00:00","modifiedAt":"2026-04-01T13:45:55.451+00:00","affected":[{"ecosystem":"Vendor product","name":"locutus","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"locutusjs\",\n                    \"product\": \"locutus\",\n                    \"versions\": [\n                        {\n                            \"version\": \">= 2.0.39, < 3.0.25\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N","score":6.3,"severity":"MEDIUM"}],"references":["https://github.com/locutusjs/locutus/security/advisories/GHSA-vc8f-x9pp-wf5p","https://github.com/locutusjs/locutus/pull/597","https://github.com/locutusjs/locutus/commit/345a6211e1e6f939f96a7090bfeff642c9fcf9e4","https://github.com/locutusjs/locutus/releases/tag/v3.0.25"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-33994","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-33994","identifiers":["CVE-2026-33994"]},"retained":false,"historicalAffected":[]}],"coverage":[]}