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Mattermost: security advisories, deprecations and releases
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- Items, 90 days
- 7
- Critical
- 0
- Last critical
- none
- This week
- 0
Deprecations 6
- MEDIUM ACT BY 15 JAN 2027 endoflife.date · 22 Oct 2026
Mattermost 12.0 reaches end of life on 2027-01-15
Mattermost 12.0 reaches end of life on 2027-01-15, as listed by endoflife.date.
- HIGH ACT BY 15 NOV 2026 endoflife.date · 16 Oct 2026
Mattermost 11.10 reaches end of life on 2026-11-15
Mattermost 11.10 reaches end of life on 2026-11-15, as listed by endoflife.date.
- HIGH ACT BY 15 OCT 2026 endoflife.date · 15 Oct 2026
Mattermost 11.9 has reached end of life
Mattermost 11.9 reached end of life on 2026-10-15, as listed by endoflife.date.
- HIGH ACT BY 15 OCT 2026 endoflife.date · 2 Oct 2026
Mattermost 11.9 reaches end of life on 2026-10-15
Mattermost 11.9 reaches end of life on 2026-10-15, as listed by endoflife.date.
- MEDIUM ACT BY 15 NOV 2026 endoflife.date · 2 Oct 2026
Mattermost 11.10 reaches end of life on 2026-11-15
Mattermost 11.10 reaches end of life on 2026-11-15, as listed by endoflife.date.
- MEDIUM ACT BY 15 DEC 2026 endoflife.date · 2 Oct 2026
Mattermost 11.11 reaches end of life on 2026-12-15
Mattermost 11.11 reaches end of life on 2026-12-15, as listed by endoflife.date.
Releases 1
- INFO endoflife.date · 22 Oct 2026
Mattermost 12.0 released
Mattermost 12.0 was released on 2026-10-16.
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