What is CVE-2023-5330?

CVE-2023-5330 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-2023-5330?

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

Resource exhaustion in Mattermost

CVE-2023-5330

Mattermost fails to enforce a limit for the size of the cache entry for OpenGraph data allowing an attacker to send a specially crafted request to the /api/v4/opengraph filling the cache and turning the server unavailable.

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 (40.3th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 40th percentile — 40.3% 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)

References

mattermost.com/security-updates (Vendor Advisory)

Frequently asked questions

What is CVE-2023-5330?: CVE-2023-5330 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-2023-5330?: Medium severity. CVSS v3 base score is 4.3 out of 10.