CVE-2017-18907 json
Mattermost Server vulnerable to XSS through channel headers
published 2020-06-19 6 y ago modified 2026-06-17 4 mo ago also GHSA-42x9-rr3c-gr59 , GO-2026-4459 , EUVD-2017-9997
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.7%
- EPSS 0.7% chance of exploitation in 30 days, percentile 53%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- go github.com/mattermost/mattermost-server 3.9.2-0.20170714014920-312269ad0bd1, 3.10.2, 3.10.2+incompatible
- mattermost mattermost_server 3.9.2, 3.10.2
- govulncheck-vulndb openSUSE Leap 15.6 0.0.20260226T182644-150000.1.149.1
suse advisories SUSE-SU-2026:0757-1
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
Exploit prediction
0.69% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
| GitHub | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/mattermost/mattermost-server | <3.9.2-0.20170714014920-312269ad0bd1 >=3.10.0, <3.10.2 >=3.10.0+incompatible, <3.10.2+incompatible |
3.9.2-0.20170714014920-312269ad0bd1 3.10.2 3.10.2+incompatible |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/mattermost/mattermost/commit/312269ad0bd166174f07f9df7391fce714601600
web
-
github.com
/mattermost/mattermost/commit/4519b03d95e8bfe1b2f74094673ae1a2f39f6b47
web
-
github.com
/mattermost/mattermost/commit/a18479df0940be8503c9b88993490741793eba9e
web
-
mattermost.com
/security-updates/
vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2017-18907
advisory
-
github.com
/mattermost/mattermost
package
-
mattermost.com
/security-updates
web
-
github.com
/advisories/GHSA-42x9-rr3c-gr59
advisory
Sources
- CVE List CVE-2017-18907
- GitHub Advisory GHSA-42x9-rr3c-gr59
- NVD CVE-2017-18907
- OSV GO-2026-4459
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.