CVE Catalog

CVE-2026-93753

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.36%

30th percentile - higher than 30% of all known CVEs

Summary

deepmerge through 4.3.1 contains a prototype poisoning vulnerability in the mergeObject() function that fails to properly validate keys being written to target objects. Attackers can supply malicious source objects in merge operations to inject attacker-controlled properties into the returned object's prototype, causing applications to inherit unintended values when accessing properties without own-property checks.

Risk Assessment

The risk includes the possibility of modifying object prototypes, which may lead to unauthorized changes in application behavior, potentially enabling attacks such as application takeover or data leakage.

Recommendation

It is recommended to update the deepmerge library to the latest patched version and avoid merging untrusted objects without proper key validation.

Related vulnerabilities

Original NVD description (English source)

deepmerge through 4.3.1 contains a prototype poisoning vulnerability in the mergeObject() function that fails to properly validate keys being written to target objects. Attackers can supply malicious source objects in merge operations to inject attacker-controlled properties into the returned object's prototype, causing applications to inherit unintended values when accessing properties without own-property checks.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS