CVE-2025-69873_CVE-2025-69873

7.5 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

ajv (Another JSON Schema Validator) through version 8.17.1 is vulnerable to Regular Expression Denial of Service (ReDoS) when the $data option is enabled. The pattern keyword accepts runtime data via JSON Pointer syntax ($data reference), which is passed directly to the JavaScript RegExp() constructor without validation. An attacker can inject a malicious regex pattern (e.g., "^(a|a)*$") combined with crafted input to cause catastrophic backtracking. A 31-character payload causes approximately 44 seconds of CPU blocking, with each additional character doubling execution time. This enables complete denial of service with a single HTTP request against any API using ajv with $data: true for dynamic schema validation.

Basic Information

ID CVE-2025-69873

Source mitre

Published Feb 11, 2026 at 00:00

Modified Feb 12, 2026 at 15:14

Affected Product

Vendor n/a

Product n/a

Version n/a

Affected Versions n/a n/a n/a

CWE Classification

CWE-400

References

github.com /EthanKim88/ethan-cve-disclosures/blob/main/CVE-2025-69873-ajv-ReDoS.md

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    "published": "2026-02-11T00:00:00.000Z",
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