{"id":"CVE-2026-12644","details":"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.","aliases":["GHSA-87mf-gv2c-c62c"],"modified":"2026-08-12T03:51:11.166809129Z","published":"2026-06-19T05:00:00.666Z","database_specific":{"cna_assigner":"snyk","cwe_ids":["CWE-248"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12644.json"},"references":[{"type":"WEB","url":"https://gist.github.com/igorg1312/775fa00114c4d47df6ae0551779ab407"},{"type":"WEB","url":"https://security.snyk.io/vuln/SNYK-JS-TSDEEPMERGE-17339141"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12644.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12644"},{"type":"FIX","url":"https://github.com/voodoocreation/ts-deepmerge/commit/305a05831a462fb2c353d3cbbff55a0733286f8c"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/voodoocreation/ts-deepmerge","events":[{"introduced":"0"},{"fixed":"305a05831a462fb2c353d3cbbff55a0733286f8c"}],"database_specific":{"source":["AFFECTED_FIELD","DESCRIPTION","REFERENCES"],"extracted_events":[{"introduced":"0"},{"fixed":"8.0.0"}]}}],"versions":["7.0.3","7.0.2","7.0.1","7.0.0","6.2.1","6.2.0","6.1.0","6.0.3","6.0.2","6.0.1","6.0.0","5.0.0","4.0.0","3.0.0","2.0.7","2.0.6","2.0.5","2.0.4","2.0.3","2.0.2","2.0.1","2.0.0","1.1.0","1.0.8","1.0.7","1.0.6","1.0.5","1.0.4","1.0.3","1.0.2","1.0.1","1.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-12644.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"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"}]}