Description
Seroval facilitates JavaScript value stringification, including complex structures beyond JSON.stringify capabilities. Prior to 1.6.8, fromJSON rebuilds an AsyncIteratorFactoryInstance by calling source.on(listener) without requiring source to be a genuine internal stream. With untrusted Seroval input and an application plugin that returns a callable value or an object exposing an on method, a crafted node can reuse an identifier so the deserializer invokes the plugin-produced value. This is an incomplete-fix variant of CVE-2026-59940. The resulting confidentiality, integrity, or availability impact depends on the behavior exposed by the application plugin. This issue is fixed in version 1.6.8.
References4
Metrics
- CVSS 3.1
-
7.3
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - EPSS — exploit probability
- 0% percentile: 28 · as of 8 November 2026
- CWE
- CWE-502
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