What is CVE-2026-13055?

CVE-2026-13055 is a medium-severity vulnerability in MongoDB, classified under Reachable Assertion. CVSS score: 6.5/10. Published 2026-07-22.

How severe is CVE-2026-13055?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in MongoDB

CVE-2026-13055

The `$_internalIndexKey` aggregation expression can be used by any authenticated user to crash a MongoDB server (mongod). The expression fails to handle compound wildcard index specifications, triggering an internal consistency check that aborts the server process. The user must be able to run an aggregation pipeline.

EPSS: 0.003 (20.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Mongodb
Mongodb Server — versions 7.0, 8.0, 8.2.0

Weakness classification (CWE)

CWE-617 — Reachable Assertion

References

cna@mongodb.com (Issue Tracking, Vendor Advisory)

Frequently asked questions

What is CVE-2026-13055?: CVE-2026-13055 is a medium-severity vulnerability in MongoDB, classified under Reachable Assertion. CVSS score: 6.5/10. Published 2026-07-22.
How severe is CVE-2026-13055?: Medium severity. CVSS v3 base score is 6.5 out of 10.