CVE-2026-42040
Axios: Null Byte Injection via Reverse-Encoding in AxiosURLSearchParams
LOW 3.7EPSS 0.3%
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.
- Affected
- axios
- CVSS v3.1 GITHUB
- 3.7 LOW
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N - EPSS
- 0.26% chance of exploitation in the next 30 days, 17th percentile
- Published
- 2026-04-24
- Updated
- 2026-04-27