CVE-2026-104846

Seroval facilitates JS value stringification, including complex structures beyond JSON.stringify capabilities. From 0.12.0 until 1.6.2, fromJSON deserialization of a fulfilled Promise control node can pass a plugin-produced callable-bearing thenable to a native Promise resolver. ECMAScript thenable assimilation then invokes the callable unexpectedly, allowing attacker-controlled JSON to trigger code in applications using plugin-capable Seroval releases. This path bypasses the Promise resolver type-confusion remediation in version 1.5.3 for CVE-2026-59940 because the unexpected invocation occurs through native Promise settlement after the referenced value is deserialized. This issue is fixed in version 1.6.2.

CVSS 3.1

9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

0.3% chance of exploitation in the next 30 days; higher than 27% of CVEs (scores of 2026-10-25)

CWE

CWE-843

Published

2026-10-02

Modified

2026-10-05

Record from

the NVD, synced 2026-10-19

Packages (OSV)

References

• https://github.com/lxsmnsyc/seroval/commit/f1ffcc96d259f9b5b3d71feb262b58240c90e7b7
• https://github.com/lxsmnsyc/seroval/security/advisories/GHSA-p6vx-979v-rg4c

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