CVE-2026-23957: seroval is vulnerable to Denial of Service via array serialization

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-01-22 · updated 2026-06-17
Weakness: CWE-770

Description

seroval facilitates JS value stringification, including complex structures beyond JSON.stringify capabilities. In versions 1.4.0 and below, overriding encoded array lengths by replacing them with an excessively large value causes the deserialization process to significantly increase processing time. This issue has been fixed in version 1.4.1.

Affected products

lxsmnsyc seroval: before 1.4.1 — fixed in 1.4.1

How to fix

Upgrade to a fixed version: lxsmnsyc seroval 1.4.1. Check the vendor advisory for mitigations.

References

https://github.com/lxsmnsyc/seroval/commit/ce9408ebc87312fcad345a73c172212f2a798060
https://github.com/lxsmnsyc/seroval/security/advisories/GHSA-66fc-rw6m-c2q6

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