HIGHCVSS v3.1 7.1Vulnerability

CVE-2026-16453

Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to verify the integrity of the SAML RelayState POST parameter which allows an authenticated SAML user to join any team, including invite-only teams, via forging the team_id or invite_id fields in the RelayState.. Mattermost Advisory ID: MMSA-2026-00727

Properties

Severity
HIGH
Nvd fetched at
2026-10-20T21:14:08.448323+00:00
Epss score
0.00186
Cvss severity
HIGH
Cvss score
7.1
Retrieved at
2026-10-21T01:24:48+00:00
Last source
FIRST EPSS
Score
7.1
Cvss version
3.1
Cve id
CVE-2026-16453
Cvss vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
First seen by Signal
2026-10-18T13:39:03+00:00
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
Published at
2026-10-16T08:17:12.640
Last modified
2026-10-16T19:23:18.623
Epss percentile
0.07767

Related Entities (1)

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CVE-2026-16453 (CVSS v3.1 7.1) — Ninja Signal Threat Intelligence | Ninja Signal