Reachable assertion in MongoDB Server - CVE-2026-8843
Published: August 18, 2026
Vulnerability identifier: #VU144158
CSH Severity: Low
CVSS v4: 7.1 [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]
CVE-ID: CVE-2026-8843
CWE-ID: CWE-617
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to reachable assertion in index handling when inserting a document that triggers updating a previously created "2dsphere_bucket" or "queryable_encrypted_range" index. A remote user can create a crafted index and then insert a document to cause a denial of service.
The issue occurs when a "2dsphere_bucket" index is created on a non-timeseries bucket collection, and a similar condition exists for "queryable_encrypted_range" indices.
Affected software
MongoDB Server
How to mitigate CVE-2026-8843
Install security update from vendor's website.
MongoDB Server - addressed in versions 7.0.32, 8.0.21, 8.2.6