Vulnerability · Published Sep 8, 2026 · Assigned by mongodb

CVE-2026-82052$regexFindAll may crash mongod server when byte-matching multi-byte UTF-8 chars

Medium 6.5

In plain English

A medium-severity security flaw in MongoDB Server from MongoDB. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities).

Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.5%top 57.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

The $regexFindAll expression can be used by an authenticated user who can run aggregation pipeline stages to crash a MongoDB server (mongod). Under certain specific conditions the  regex match can start in the middle of a multi-code-unit character, triggering an assertion during query execution.

Affected products (as reported)

VendorProductVersions
MongoDB MongoDB Server 8.3.0 – before 8.3.98.0 – before 8.0.307.0 – before 7.0.41

Weakness: CWE-617 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References