SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2017-18907

XSS could occur via a channel header.

MEDIUM 6.1EPSS 0.69%

Does this matter?

Lower severity and a low EPSS score (0.69%). Track it; it rarely justifies an emergency change on its own.

Description

An issue was discovered in Mattermost Server before 4.0.0, 3.10.2, and 3.9.2. XSS could occur via a channel header.

CVSS 3.1
6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS
0.69% probability · 53th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-79
Affected
mattermost/mattermost server
Source
cve@mitre.org
EPSS trend
0%3%5%27 October 2026: 0.69%27 October 202627 October 2026

EPSS 0.7% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.