CVE-2026-42040 (GCVE-0-2026-42040)

Vulnerability from cvelistv5 – Published: 2026-04-24 17:40 – Updated: 2026-04-27 13:48
VLAI
Title
Axios: Null Byte Injection via Reverse-Encoding in AxiosURLSearchParams
Summary
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.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-27 13:48 UTC
CWE
  • CWE-116 - Improper Encoding or Escaping of Output
  • CWE-626 - Null Byte Interaction Error (Poison Null Byte)
Assigner
References
Impacted products
Vendor Product Version CPE status
axios axios Affected: >= 1.0.0, < 1.15.1
Affected: < 0.31.1
guessed Create a notification for this product.
Show details on NVD website
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