{"action":"Upgrade flat-to-nested to 1.1.2 or later.","affected":[{"fixed":"1.1.2","introduced":"0"}],"component":"flat-to-nested","cve_ids":["CVE-2026-55091"],"ecosystem":"npm","epss":0.00497,"exploited":false,"fixed_versions":["1.1.2"],"ghsa_id":"GHSA-hp36-v28f-w3r4","id":"tcs_01M5KFVM5F5HNT6PVRRM50D7H1","modified_at":"2026-06-19T21:11:28.864030Z","published_at":"2026-06-19T20:47:52Z","references":["https://osv.dev/vulnerability/GHSA-hp36-v28f-w3r4","https://github.com/joaonuno/flat-to-nested-js/security/advisories/GHSA-hp36-v28f-w3r4","https://github.com/joaonuno/flat-to-nested-js/commit/680a5ebe1194edda16fa93baaa56ff14fe0e3d7f","https://github.com/joaonuno/flat-to-nested-js"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"GHSA-hp36-v28f-w3r4","url":"https://osv.dev/vulnerability/GHSA-hp36-v28f-w3r4"}],"summary":"flat-to-nested: Prototype pollution in flat-to-nested convert() via __proto__ parent/id key"}