Use After Free in MongoDB Server

CVE-2026-82056

A race condition in MongoDB server's text index query parsing can cause a heap use-after-free read when handling upsert retry paths. Under certain concurrent index lifecycle operations, a raw pointer to internal text index metadata may be dereferenced after the underlying structures have been freed, leading to a server crash. An authenticated user with readWrite privileges can trigger this condition through specific concurrent text-search and index management operations, resulting in denial of service for all connected clients. This

Vulnerability class: Use-After-Free

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-82056?
CVE-2026-82056 is a medium-severity vulnerability in MongoDB Server, classified under Use After Free. CVSS score: 5.3/10. Published 2026-09-08.
How severe is CVE-2026-82056?
Medium severity. CVSS v3 base score is 5.3 out of 10.