{"cve":"CVE-2026-106448","nvd":{"published":"2026-10-06T20:17:26.743","modified":"2026-10-07T17:16:47.727","status":"Awaiting Analysis","description":"StableLib is a stable library of useful TypeScript and JavaScript code. Prior to 2.0.4, the @stablelib/cbor CBOR map decoding path creates ordinary JavaScript objects and assigns attacker-controlled keys with bracket assignment. A map key named __proto__ invokes the inherited prototype setter instead of creating an ordinary own property, allowing the decoded object's prototype to contain attacker-controlled authorization or feature-flag values. Downstream code that trusts normal property lookup or merges the decoded object can therefore make security-sensitive decisions using inherited attacker data. This issue is fixed in version 2.0.4.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N","score":8.9},"cvss_v3":null,"cwes":["CWE-1321"],"references":["https://github.com/StableLib/stablelib/commit/0f153a63b7552a0e8721f640984113e419015026","https://github.com/StableLib/stablelib/releases/tag/@stablelib/cbor@2.0.4","https://github.com/StableLib/stablelib/security/advisories/GHSA-w48f-fwg7-ww6p"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:58:01.639778232+00:00"},"epss":{"cve":"CVE-2026-106448","score":0.00401,"percentile":0.3407,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-w48f-fwg7-ww6p","url":"https://osv.dev/vulnerability/GHSA-w48f-fwg7-ww6p","summary":"@stablelib/cbor: Prototype poisoning via `__proto__` map keys in CBOR decoding","modified":"2026-10-07T10:56:10.181649137Z","packages":[{"ecosystem":"npm","name":"@stablelib/cbor","purl":"pkg:npm/%40stablelib/cbor","ranges":["<2.0.3"],"fixed":["2.0.3"]}]}],"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."]}