{"id":"CVE-2026-42040","summary":"Axios: Null Byte Injection via Reverse-Encoding in AxiosURLSearchParams","details":"Axios is a promise based HTTP client for the browser and Node.js. Prior to 1.15.1 and 0.31.1, the encode() function in lib/helpers/AxiosURLSearchParams.js contains a character mapping (charMap) at line 21 that reverses the safe percent-encoding of null bytes. After encodeURIComponent('\\x00') correctly produces the safe sequence %00, the charMap entry '%00': '\\x00' converts it back to a raw null byte. Primary impact is limited because the standard axios request flow is not affected. This vulnerability is fixed in 1.15.1 and 0.31.1.","aliases":["GHSA-xhjh-pmcv-23jw"],"modified":"2026-05-18T06:00:10.364675328Z","published":"2026-04-24T17:40:31.125Z","related":["CGA-qgpm-gpvr-4vw2"],"database_specific":{"cwe_ids":["CWE-116","CWE-626"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42040.json","cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42040.json"},{"type":"ADVISORY","url":"https://github.com/axios/axios/security/advisories/GHSA-xhjh-pmcv-23jw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42040"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/axios/axios","events":[{"introduced":"484aa4fe6addccbd32206a31eb3d2d000843066e"},{"fixed":"a589dc525af12e0fabef7d6e5be028ad433eee31"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-42040.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N"}]}