CVE-2026-82052 PUBLISHED

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

Assigner: mongodb
Reserved: 27.08.2026 Published: 08.09.2026 Updated: 08.09.2026

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.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/AU:Y/R:A
CVSS Score: 7.1

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	Low
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 6.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	Low	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	MongoDB
Product	MongoDB Server
Versions	Default: unaffected affected from 8.3.0 to 8.3.9 (excl.) affected from 8.0 to 8.0.30 (excl.) affected from 7.0 to 7.0.41 (excl.)

References

https://jira.mongodb.org/browse/SERVER-124077

Problem Types

CWE-617 Reachable assertion CWE