CVE-2026-15754

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.24% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 15.6% of scored records. A rank, not a probability.

NVD base score

4.2 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N

NVD analysis status

Analyzed. NVD last modified this record on 2026-08-18.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-08-17 14:36Z2 MO AGO

Last updated

2026-08-17 15:25Z2 MO AGO

Reserved

2026-07-14

Assigning CNA

Mattermost

Record state

PUBLISHED

Severity

Medium (CVSS 4.2)

CNA CVSS vector

CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N

Weaknesses

• CWE-863Incorrect AuthorizationClass

Data version

5.2

Document digest

3188da8b15ac03c10a3ca37fa2e2d5597de84fbd3884c63dfcf84229345779f6

• mattermost.comMMSA-2026-00718https://mattermost.com/security-updatesvendor-advisory