The vulnerability of the Mattermost instant messaging application, related to synchronization errors when using a shared resource (“Race Situation”), allows a violator to compromise the confidentiality and integrity of the protected information.
🗓️ 20 Apr 2026 00:00:00Reported by FSTEC of Russia — Information Security Threat DatabaseType 
bdu_fstec🔗 bdu.fstec.ru👁 4 Views
| Reporter | Title | Published | Views | Family All 17 |
|---|---|---|---|---|
 | CVE-2026-3590 | 15 Apr 202611:00 | – | attackerkb |
 | CVE-2026-3590 | 15 Apr 202615:28 | – | circl |
 | Mattermost 安全漏洞 | 15 Apr 202600:00 | – | cnnvd |
 | CVE-2026-3590 | 15 Apr 202611:00 | – | cve |
 | CVE-2026-3590 Race Condition in Guest Magic Link Authentication Allows Token Reuse | 15 Apr 202611:00 | – | cvelist |
 | EUVD-2026-22915 | 17 Apr 202615:31 | – | euvd |
 | Mattermost has session spoofing due to lack of single-use consumption of guest magic link tokens enforcement | 17 Apr 202615:31 | – | github |
 | Mattermost Server 10.11.x <= 10.11.13 / 11.3.x < 11.3.3 / 11.4.x < 11.4.3 / 11.5.x < 11.5.1 / 11.6.0 Multiple Vulnerabilities (MMSA-2026-00624 / MMSA-2026-00625) | 24 Apr 202600:00 | – | nessus |
 | CVE-2026-3590 | 15 Apr 202612:16 | – | nvd |
 | CVE-2026-3590 Race Condition in Guest Magic Link Authentication Allows Token Reuse | 15 Apr 202611:00 | – | osv |
10
Node
OR
| Source | Link |
|---|---|
| mattermost | www.mattermost.com/security-updates |
| web | www.web.nvd.nist.gov/view/vuln/detail |
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20 Apr 2026 00:00Current
5.8Medium risk
Vulners AI Score5.8
CVSS 26.4
CVSS 36.5
EPSS0.00145