Prototype pollution in devalue - CVE-2026-30226
Published: April 24, 2026
Vulnerability identifier: #VU127522
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-30226
CWE-ID: CWE-1321
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Rich Harris
Affected software:
devalue
devalue
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improperly controlled modification of object prototype attributes in devalue.parse and devalue.unflatten when parsing maliciously crafted payloads. A remote attacker can supply a specially crafted payload to cause a denial of service.
The issue may also lead to type confusion.
How to mitigate CVE-2026-30226
Install security update from vendor's website.