Critical severity · published Jan 21, 2026
CVE-2026-23736
seroval Affected by Prototype Pollution via JSON Deserialization
9.8
CVSS
0.3%
EPSS
No
On KEV
Description
seroval facilitates JS value stringification, including complex structures beyond JSON.stringify capabilities. In versions 1.4.0 and below, due to improper input validation, a malicious object key can lead to prototype pollution during JSON deserialization. This vulnerability affects only JSON deserialization functionality. This issue is fixed in version 1.4.1.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 22% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SE
seroval · lxsmnsyc
< 1.4.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-23736
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-23736
Patch
https://github.com/lxsmnsyc/seroval/commit/ce9408ebc87312fcad345a73c172212f2a798060
Vendor Advisory
https://github.com/lxsmnsyc/seroval/security/advisories/GHSA-hj76-42vx-jwp4
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