MEDIUMCVSS v3.1 4.3Vulnerability
CVE-2026-18799
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 restrict Slack import account binding to system administrator-initiated imports which allows an authenticated attacker with team admin privileges to force-add existing Mattermost users to their team and forge posts attributed to those users' identities via a crafted Slack export containing target users' email addresses.. Mattermost Advisory ID: MMSA-2026-00757
Properties
- Severity
- MEDIUM
- Nvd fetched at
- 2026-10-20T21:14:08.448323+00:00
- Epss score
- 0.00152
- Cvss score
- 4.3
- Cvss severity
- MEDIUM
- Retrieved at
- 2026-10-21T01:24:49+00:00
- Last source
- FIRST EPSS
- Score
- 4.3
- Cvss version
- 3.1
- Cve id
- CVE-2026-18799
- Cvss vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/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:N/I:L/A:N
- Published at
- 2026-10-16T08:17:13.073
- Last modified
- 2026-10-16T19:23:18.623
- Epss percentile
- 0.03961
Related Entities (1)
HAS_WEAKNESS (1)
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