Answer in brief
CVE-2026-59940 records a Unknown severity vulnerability in Seroval: `seroval.fromJSON()` Promise resolver type confusion invokes attacker-controlled methods during deserialization. The current sources do not mark it as known exploited. The current feed maps lxsmnsyc/seroval (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps lxsmnsyc/seroval (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| lxsmnsyc/serovalgeneric | < 1.5.3 | Not reported |
Published upstream
Aug 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 18, 2026
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.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-59940 records a Unknown severity vulnerability in Seroval: `seroval.fromJSON()` Promise resolver type confusion invokes attacker-controlled methods during deserialization. The current sources do not mark it as known exploited. The current feed maps lxsmnsyc/seroval (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps lxsmnsyc/seroval (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| lxsmnsyc/serovalgeneric | < 1.5.3 | Not reported |
Published upstream
Aug 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 18, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 18, 2026
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.
Quoted source text, attributed separately from HOL analysis.