CVE-2026-42040

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.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/axios/axios/security/advisories/GHSA-xhjh-pmcv-23jw	Exploit Mitigation Vendor Advisory
https://github.com/axios/axios/security/advisories/GHSA-xhjh-pmcv-23jw	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:axios:axios::::::node.js::*
	cpe:2.3:a:axios:axios::::::node.js::*

History

27 Apr 2026, 20:09

Type	Values Removed	Values Added
First Time		Axios axios Axios
CPE		cpe:2.3:a:axios:axios::::::node.js::*
References	~~() https://github.com/axios/axios/security/advisories/GHSA-xhjh-pmcv-23jw -~~	() https://github.com/axios/axios/security/advisories/GHSA-xhjh-pmcv-23jw - Exploit, Mitigation, Vendor Advisory

27 Apr 2026, 14:16

Type	Values Removed	Values Added
References	~~() https://github.com/axios/axios/security/advisories/GHSA-xhjh-pmcv-23jw -~~	() https://github.com/axios/axios/security/advisories/GHSA-xhjh-pmcv-23jw -

24 Apr 2026, 18:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-24 18:16

Updated : 2026-06-17 10:47

NVD link : CVE-2026-42040

Mitre link : CVE-2026-42040

CVE.ORG link : CVE-2026-42040

JSON object : View

Products Affected

axios

axios

CWE

CWE-116

Improper Encoding or Escaping of Output

CWE-626

Null Byte Interaction Error (Poison Null Byte)

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