CVE-2019-20888
An issue was discovered in Mattermost Server before 5.7, 5.6.3, 5.5.2, and 4.10.5. It allows...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2019-20888- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-401
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2019-20888- Updated
- 2026-11-02
EUVDEUVD-2019-11425 No score
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.
- Record
EUVD-2019-11425- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-xj4q-jrgv-5q6g No score
An issue was discovered in Mattermost Server before 5.7, 5.6.3, 5.5.2, and 4.10.5. It allows...
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.
- Record
GHSA-xj4q-jrgv-5q6g- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2019-20888- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2019-20888 is a high vulnerability (CVSS 7.5) in Mattermost Server, published June 19, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.11%, the 66th percentile. No source names a fixed version.