CVE-2026-2578
published 2026-03-16CVE-2026-2578: Mattermost versions 11.3.x <= 11.3.0 fail to preserve the redacted state of burn-on-read posts during deletion which allows channel members to access…
PriorityP421medium4.3CVSS 3.1
AVNACLPRLUINSUCLINAN
EPSS
0.22%
12.5th percentile
Mattermost versions 11.3.x <= 11.3.0 fail to preserve the redacted state of burn-on-read posts during deletion which allows channel members to access unrevealed burn-on-read message contents via the WebSocket post deletion event.. Mattermost Advisory ID: MMSA-2026-00579
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| github.com | mattermost_mattermost-server | >= 0 < 5.3.2-0.20260127062706-c6b205f0d770 | 5.3.2-0.20260127062706-c6b205f0d770 |
| github.com | mattermost_mattermost-server | >= 10.11.0-rc1 < 10.11.11 | 10.11.11 |
| github.com | mattermost_mattermost-server | >= 10.11.0-rc1+incompatible < 10.11.11+incompatible | 10.11.11+incompatible |
| github.com | mattermost_mattermost-server | >= 11.2.0-rc1 < 11.2.3 | 11.2.3 |
| github.com | mattermost_mattermost-server | >= 11.2.0-rc1+incompatible < 11.2.3+incompatible | 11.2.3+incompatible |
| github.com | mattermost_mattermost-server | >= 11.3.0-rc1 < 11.3.1 | 11.3.1 |
| github.com | mattermost_mattermost-server | >= 11.3.0-rc1+incompatible < 11.3.1+incompatible | 11.3.1+incompatible |
| github.com | mattermost_mattermost_server_v8 | >= 0 < 8.0.0-20260127062706-c6b205f0d770 | 8.0.0-20260127062706-c6b205f0d770 |
| mattermost | mattermost | 11.3.0 – 11.3.0 | — |
| mattermost | mattermost_server | >= 11.3.0 < 11.3.1 | 11.3.1 |
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OSV
Mattermost fails to preserve the redacted state of burn-on-read posts during deletion in github.com/mattermost/mattermost-server
osv·2026-03-23
CVE-2026-2578 Mattermost fails to preserve the redacted state of burn-on-read posts during deletion in github.com/mattermost/mattermost-server
Mattermost fails to preserve the redacted state of burn-on-read posts during deletion in github.com/mattermost/mattermost-server
Mattermost fails to preserve the redacted state of burn-on-read posts during deletion in github.com/mattermost/mattermost-server.
NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions.
(If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.)
The additional affected modules and versions are: github.com/mattermost/mattermost-server/v5 before v5.3.2-0.20260127062706-c6b205f0d770.
GHSA
Mattermost fails to preserve the redacted state of burn-on-read posts during deletion
ghsa·2026-03-16
CVE-2026-2578 [MEDIUM] CWE-201 Mattermost fails to preserve the redacted state of burn-on-read posts during deletion
Mattermost fails to preserve the redacted state of burn-on-read posts during deletion
Mattermost versions 11.3.x <= 11.3.0 fail to preserve the redacted state of burn-on-read posts during deletion which allows channel members to access unrevealed burn-on-read message contents via the WebSocket post deletion event. Mattermost Advisory ID: MMSA-2026-00579
OSV
Mattermost fails to preserve the redacted state of burn-on-read posts during deletion
osv·2026-03-16
CVE-2026-2578 [MEDIUM] Mattermost fails to preserve the redacted state of burn-on-read posts during deletion
Mattermost fails to preserve the redacted state of burn-on-read posts during deletion
Mattermost versions 11.3.x <= 11.3.0 fail to preserve the redacted state of burn-on-read posts during deletion which allows channel members to access unrevealed burn-on-read message contents via the WebSocket post deletion event. Mattermost Advisory ID: MMSA-2026-00579
No detection rules found.
No public exploits indexed.
2026-03-16
Published