CVE-2026-106448
StableLib is a stable library of useful TypeScript and JavaScript code
- Risk score
- 65/100
- CVSS
- 8.9 v4.0
- Exploit chance (30 days)
- 0.4%
- Published
- 6 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- 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 or…
- Affected
- See advisory
- Fix
- Upgrade the product to 2.0.4 or later.
- Exploitation
- No known exploitation
Why it is Amber
- CVSS 8.9 high
- Remotely exploitable without logging in
References
Original 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.
Last activity 6 Oct 2026. Patch Forecast updates every hour.