CVE-2026-118383

Pre-authentication use-after-free in MongoDB Server replica set primary catch-up

Published Nov 10, 2026 CVSS 4.0 · 9.5 Critical EPSS < 1% KEV · Not listed
Description
A use-after-free in the replication component of MongoDB Server can occur when a newly elected replica set primary completes catch-up. The condition can be caused by requests that do not require authentication, and may result in the server terminating unexpectedly or, under certain conditions, arbitrary code execution in the context of the server process. Replica set members are affected, including the shard and config server replica set members of sharded clusters; standalone mongod instances are not.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Mongodb
Mongodb mongodb Server
Vendors & Products Mongodb
Mongodb mongodb Server
Type Values Removed Values Added
Description A use-after-free in the replication component of MongoDB Server can occur when a newly elected replica set primary completes catch-up. The condition can be caused by requests that do not require authentication, and may result in the server terminating unexpectedly or, under certain conditions, arbitrary code execution in the context of the server process. Replica set members are affected, including the shard and config server replica set members of sharded clusters; standalone mongod instances are not.
Title Pre-authentication use-after-free in MongoDB Server replica set primary catch-up
Weaknesses CWE-416
References
Metrics cvssV3_1

{'score': 9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H'}

cvssV4_0

{'score': 9.5, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
mongodb
Published
Updated
Nov 10, 2026, 8:23 PM
Reserved
Oct 28, 2026, 2:46 AM
Status
Awaiting Analysis
Published
Nov 10, 2026, 9:18 PM
Modified
Nov 10, 2026, 10:08 PM