Skip to content

Malicious inputs to "$toMillis" function can cause resource exhaustion

High
andrew-coleman published GHSA-86vw-mfpg-wwv9 May 29, 2026

Package

npm jsonata (npm)

Affected versions

<2.2.0

Patched versions

2.2.0

Description

Impact

In JSONata <v2.2.0, it is possible to craft non-matching inputs to the $toMillis function that cause superlinear backtracking in the ISO-8601 validation regex. This may lead to denial of service in applications that evaluate user-provided JSONata expressions.

Patches

This issue has been addressed in JSONata version >= 2.2.0 via fixes that include #782 and #793. Applications that evaluate user-provided expressions should update ASAP to prevent exploitation.

References

https://github.com/jsonata-js/jsonata/releases/tag/v2.2.0

Credit

Thank you to Doruk Tan Öztürk for disclosing this issue.

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVE ID

CVE-2026-52746

Weaknesses

Inefficient Regular Expression Complexity

The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles. Learn more on MITRE.

Credits