Access of Resource Using Incompatible Type ('Type Confusion') Affecting seroval package, versions >=0.12.0 <1.6.2
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-JS-SEROVAL-20417221
- published4 Oct 2026
- disclosed2 Oct 2026
- creditAyoub Elaich
Introduced: 2 Oct 2026
NewCVE-2026-104846 (opens in a new tab)How to fix?
Upgrade seroval to version 1.6.2 or higher.
Overview
seroval is a Stringify JS values
Affected versions of this package are vulnerable to Access of Resource Using Incompatible Type ('Type Confusion') via the deserializePromise and deserializePromiseFulfill functions in deserializer.ts, where a thenable object (an object with a then property that is a function) can be passed as the resolved or rejected value of a deserialized Promise node. Because the deserializer previously did not check whether the deserialized value was thenable before passing it to the deferred resolver, an attacker supplying a malicious serialized payload can cause the Promise resolution to follow the attacker-controlled thenable, enabling prototype pollution of the JavaScript runtime environment. This allows full compromise of object prototypes, leading to arbitrary property injection across all objects in the process.