What is CVE-2023-5333?

CVE-2023-5333 is a medium-severity vulnerability in Mattermost, classified under Uncontrolled Resource Consumption. CVSS score: 4.3/10. Published 2023-10-09.

How severe is CVE-2023-5333?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Resource exhaustion in Mattermost

CVE-2023-5333

Mattermost fails to deduplicate input IDs allowing a simple user to cause the application to consume excessive resources and possibly crash by sending a specially crafted request to /api/v4/users/ids with multiple identical IDs.

Vulnerability class: DoS (Denial of Service)

Published 2023-10-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.005 (39.9th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 39.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Mattermost — versions 0, 7.8.11, 8.0.3
Mattermost Server

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption

References

mattermost.com/security-updates (Vendor Advisory)

Frequently asked questions

What is CVE-2023-5333?: CVE-2023-5333 is a medium-severity vulnerability in Mattermost, classified under Uncontrolled Resource Consumption. CVSS score: 4.3/10. Published 2023-10-09.
How severe is CVE-2023-5333?: Medium severity. CVSS v3 base score is 4.3 out of 10.