A AegiFlow
MEDIUMCVSS 4.3

CVE-2026-18799

CVE-2026-18799 updated by NVD

Modified
2026-10-31
Sources
nvd

Summary

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

References

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

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