CVE-2017-18878
mediumpriority · track · 17EPSS 0.008 · 56 %ileEUUSEPSS · scored 2026-10-28
An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. Knowledge of a session ID allows revoking another user's session.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (8)
Products and version ranges known to be affected.
- mattermost mattermost server4.2.0 → 4.2.1nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
- Go github.com/mattermost/mattermost-server< 4.1.2-0.20171004201910-6be8113eb60cosvUSpkg:golang/github.com/mattermost/mattermost-server
- Go github.com/mattermost/mattermost-server4.2.0-rc1 → 4.2.1-0.20171004192657-8fbbd688ea24osvUSpkg:golang/github.com/mattermost/mattermost-server
- Go github.com/mattermost/mattermost-server4.3.0-rc1 → 4.3.0osvUSpkg:golang/github.com/mattermost/mattermost-server
- Go github.com/mattermost/mattermost-server4.3.0-rc1+incompatible → 4.3.0+incompatibleosvUSpkg:golang/github.com/mattermost/mattermost-server
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-h564-6gc2-fcc6Mattermost Server allows users with a session ID to revoke another users' session2022-05-24ghsa · osvUS
An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. Knowledge of a session ID allows revoking another user's session.
- GO-2025-4191Mattermost Server allows users with a session ID to revoke another users' session in github.com/mattermost/mattermost-server2025-12-15vendor · osvUS
Mattermost Server allows users with a session ID to revoke another users' session 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 before v4.1.2-0.20171004201910-6be8113eb60c, before v4.2.1-0.20171004192657-8fbbd688ea24.
also known as (5)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (4)
External citations — patches, advisories, analysis.
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