CVE-2017-18873

mediumpriority · track · 21EPSS 0.011 · 66 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.11% (66th) EPSS

CVSS 5 · medium

Is it mine?

10 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. It allows attackers to cause a denial of service (channel invisibility) via a misformatted post.

cvss

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

5.3

010

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

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lprimary · NVD / NIST USexploitability 3.9 · impact 1.4

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · OSV

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-20US

affected products (10)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
mattermost mattermost server< 4.1.2nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server4.2.0 → 4.2.1nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
mattermost mattermost server= 4.3.0nvdUScpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
Go github.com/mattermost/mattermost-server< 4.1.2-0.20171013141717-ee57a5829ab1osvUSpkg:golang/github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost-server< 4.1.2-0.20171013141717-ee57a5829ab1+incompatibleosvUSpkg:golang/github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost-server4.2.0 → 4.2.1-0.20171013140502-b3e4b0ac9168osvUSpkg:golang/github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost-server4.2.0+incompatible → 4.2.1-0.20171013140502-b3e4b0ac9168+incompatibleosvUSpkg: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-x6mw-hf2j-vqpcMattermost Server is vulnerable to channel invisibility DoS via misformatted post2022-05-24ghsa · osvUS
An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows attackers to cause a denial of service (channel invisibility) via a misformated post.
GO-2026-4282Mattermost Server is vulnerable to channel invisibility DoS via misformatted post in github.com/mattermost/mattermost-server2026-02-26vendor · osvUS
Mattermost Server is vulnerable to channel invisibility DoS via misformatted post 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 v4.1.2-0.20171013141717-ee57a5829ab1, before v4.2.1-0.20171013140502-b3e4b0ac9168.

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv nvd NVD CVE.org MITRE

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

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references (4)

External citations — patches, advisories, analysis.

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