CVE-2026-12644

Versions of the package ts-deepmerge before 8.0.0 are vulnerable to Uncaught Exception due to the improper handling of built-in Object.prototype methods (such as toString, valueOf). When user-controlled input contains these keys with non-function values, the resulting merged object becomes broken — any string context operation throws a TypeError, crashing the application.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://gist.github.com/igorg1312/775fa00114c4d47df6ae0551779ab407
https://github.com/voodoocreation/ts-deepmerge/commit/305a05831a462fb2c353d3cbbff55a0733286f8c
https://security.snyk.io/vuln/SNYK-JS-TSDEEPMERGE-17339141
https://gist.github.com/igorg1312/775fa00114c4d47df6ae0551779ab407

Configurations

No configuration.

History

22 Jun 2026, 16:16

Type	Values Removed	Values Added
References	~~() https://gist.github.com/igorg1312/775fa00114c4d47df6ae0551779ab407 -~~	() https://gist.github.com/igorg1312/775fa00114c4d47df6ae0551779ab407 -

19 Jun 2026, 06:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-19 06:17

Updated : 2026-06-22 16:16

NVD link : CVE-2026-12644

Mitre link : CVE-2026-12644

CVE.ORG link : CVE-2026-12644

JSON object : View

Products Affected

No product.

CWE

CWE-248

Uncaught Exception

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