CVE-2026-12866

All versions of the package expr-eval are vulnerable to Code Execution via the toJSFunction() API. An attacker can execute arbitrary JavaScript by supplying crafted expressions that are compiled into native code using new Function(). Because user-controlled expressions are transformed directly into executable JavaScript, attackers can escape the intended expression sandbox and run arbitrary code within the application's context.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/silentmatt/expr-eval/blob/master/src/expression.js%23L55
https://github.com/silentmatt/expr-eval/issues/292
https://security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-17662018
https://security.snyk.io/vuln/SNYK-JS-EXPREVAL-15054690
https://security.snyk.io/vuln/SNYK-JS-EXPREVAL-15054690

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-23 05:17

Updated : 2026-07-07 19:16

NVD link : CVE-2026-12866

Mitre link : CVE-2026-12866

CVE.ORG link : CVE-2026-12866

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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