CVE-2026-59940: CWE-502: Deserialization of Untrusted Data in lxsmnsyc seroval
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.
AI Analysis
Technical Summary
The vulnerability in lxsmnsyc seroval involves improper verification during deserialization in the seroval.fromJSON() function before version 1.5.3. Specifically, attacker-controlled JSON Promise control nodes can operate on values from the general deserialization reference table without confirming they are genuine internal Promise resolver records. This can lead to deserialization side effects, including unintended server-side invocation or remote code execution if downstream frameworks register callable wrappers. This is a CWE-502 (Deserialization of Untrusted Data) and CWE-843 (Access of Resource Using Incompatible Type) issue. The vulnerability has a CVSS 3.1 score of 9.8 (critical).
Potential Impact
Successful exploitation can lead to full confidentiality, integrity, and availability compromise of affected systems due to remote code execution or unintended server-side invocation. This can allow attackers to execute arbitrary code remotely without privileges or user interaction.
Mitigation Recommendations
The vulnerability is fixed in seroval version 1.5.3. Users should upgrade to version 1.5.3 or later to remediate this issue. No other official remediation or temporary fixes are indicated. Patch status is not explicitly confirmed in vendor advisories but the description states the issue is fixed in 1.5.3.
CVE-2026-59940: CWE-502: Deserialization of Untrusted Data in lxsmnsyc seroval
Description
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.
CVSS v3.1
Score 9.8critical
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in lxsmnsyc seroval involves improper verification during deserialization in the seroval.fromJSON() function before version 1.5.3. Specifically, attacker-controlled JSON Promise control nodes can operate on values from the general deserialization reference table without confirming they are genuine internal Promise resolver records. This can lead to deserialization side effects, including unintended server-side invocation or remote code execution if downstream frameworks register callable wrappers. This is a CWE-502 (Deserialization of Untrusted Data) and CWE-843 (Access of Resource Using Incompatible Type) issue. The vulnerability has a CVSS 3.1 score of 9.8 (critical).
Potential Impact
Successful exploitation can lead to full confidentiality, integrity, and availability compromise of affected systems due to remote code execution or unintended server-side invocation. This can allow attackers to execute arbitrary code remotely without privileges or user interaction.
Mitigation Recommendations
The vulnerability is fixed in seroval version 1.5.3. Users should upgrade to version 1.5.3 or later to remediate this issue. No other official remediation or temporary fixes are indicated. Patch status is not explicitly confirmed in vendor advisories but the description states the issue is fixed in 1.5.3.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-07T18:20:06.127Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a847118c6e8be03325a97be
Added to database: 08/18/2026, 14:50:00 UTC
Last enriched: 08/18/2026, 15:04:44 UTC
Last updated: 08/19/2026, 00:28:25 UTC
Views: 10
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