CVE-2017-18878

mediumpriority · track · 17EPSS 0.008 · 56 %ileEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.78% (56th) EPSS
CVSS 4 · medium
Is it mine?
8 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · osv · nvd

EPSS · 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.

01

cvss

Technical severity, 0–10. One row per scoring source.

4.3
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04mediumAV:N/AC:L/Au:S/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 8 · impact 2.9
v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lprimary · NVD / NIST USexploitability 2.8 · impact 1.4
v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Lsecondary · OSV
v3.14mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

03

affected products (8)

Products and version ranges known to be affected.

04

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.

05

also known as (5)

Other names and identifiers for this entity.

06

sources

Which sources assert this record, and when.

published 2020-06-19modified 2026-06-17
08

references (4)

External citations — patches, advisories, analysis.

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