{"cve":"CVE-2026-12644","nvd":{"published":"2026-06-19T06:17:01.640","modified":"2026-06-23T15:42:30.483","status":"Deferred","description":"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_v4":{"vector":"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","score":5.5},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","score":5.3},"cwes":["CWE-248"],"references":["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"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:39:28.638635428+00:00"},"epss":{"cve":"CVE-2026-12644","score":0.00507,"percentile":0.43266,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-87mf-gv2c-c62c","url":"https://osv.dev/vulnerability/GHSA-87mf-gv2c-c62c","summary":"ts-deepmerge: Prototype Method Override leads to DoS","modified":"2026-06-19T21:56:30.084657Z","packages":[{"ecosystem":"npm","name":"ts-deepmerge","purl":"pkg:npm/ts-deepmerge","ranges":["<8.0.0"],"fixed":["8.0.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}