CVE-2026-106448

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

No CVSS.

References

Link	Resource
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

Configurations

No configuration.

History

06 Oct 2026, 20:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-06 20:17

Updated : 2026-10-07 17:16

NVD link : CVE-2026-106448

Mitre link : CVE-2026-106448

CVE.ORG link : CVE-2026-106448

JSON object : View

Products Affected

No product.

CWE

CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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