What’s Vulnerable › Vulnerabilities
CVE-2019-20888
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.1% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2020-06-19 · updated 2026-06-17
- Weakness: CWE-401
Description
An issue was discovered in Mattermost Server before 5.7, 5.6.3, 5.5.2, and 4.10.5. It allows attackers to cause a denial of service (memory consumption) via an outgoing webhook or a slash command integration.
Affected products
- Mattermost: before 4.10.5; from 5.5.0 before 5.5.2; from 5.6.0 before 5.6.3; 5.7.0-rc1, 5.7.0-rc2, 5.7.0-rc3, 5.7.0-rc4, 5.7.0-rc5, 5.7.0-rc6 — fixed in 4.10.5, 5.5.2, 5.6.3
How to fix
Upgrade to a fixed version: Mattermost 4.10.5, 5.5.2, 5.6.3. Check the vendor advisory for mitigations.
References
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