by Kastro
Paper/Archive/CVE-2026-59940

CVE-2026-59940

lxsmnsyc seroval — Seroval: `seroval.fromJSON()` Promise resolver type confusion invokes attacker-controlled methods during deserialization

EPSS 0.8%CVSS 9.8
critical.is priorityof 100
41
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 57.0.570 × 2011.4No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

Seroval facilitates JS value stringification, including complex structures beyond JSON.stringify capabilities. Prior to 1.5.3, seroval.fromJSON() allows attacker-controlled JSON Promise control nodes to operate on values from the general deserialization reference table without verifying genuine internal Promise resolver records, causing deserialization side effects with plugins enabled and potentially unintended server-side invocation or remote code execution when downstream frameworks register callable wrappers. This issue is fixed in version 1.5.3.

Affected

ProductAffectedFixed inSource
seroval< 1.5.3–CNA

Scores by source

GitHub_M (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refgithub.com/lxsmnsyc/seroval/security/advisories/GHSA-mv8w-475r-vwqw