cve.bz

CVE-2026-12644

5.5 mediumEPSS 0.5%

Medium (5.5). EPSS 0.5% chance of exploitation in the next 30 days. Fixed in ts-deepmerge 8.0.0.

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.

Severity

CVSS 4.0

5.5 medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

CVSS 3.1

5.3 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
EPSS
0.5% chance of exploitation in the next 30 days; higher than 43% of CVEs (scores of 2026-10-31)
CWE
CWE-248
Published
Modified
Record from
the NVD, synced

Packages (OSV)

AdvisoryEcosystemPackageAffectedFixed in
GHSA-87mf-gv2c-c62cnpmts-deepmerge<8.0.08.0.0

References

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