Technology · Go
github.com/mattermost/mattermost/server/v8 (Go) vulnerabilities
Updated . Rebuilt every hour.
Junglewise Threat Intelligence has tracked 182 vulnerabilities in github.com/mattermost/mattermost/server/v8 (Go): 0 in the last 7 days and 0 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2026-3114, was published on 25 June 2026.
- Last 7 days
- 0
- Last 90 days
- 0
- Critical, all time
- 0
- Exploited in the wild
- 0
About github.com/mattermost/mattermost/server/v8 (Go)
The server-side core of the Mattermost open-source collaboration platform.
Latest github.com/mattermost/mattermost/server/v8 (Go) vulnerabilities
- CVE-2026-3114: GO-2026-5663 - Mattermost doesn't validate decompressed archive entry sizes during file extraction in…lowCVSS 3.1EPSS 0.4%
- CVE-2026-3115: GO-2026-5512 - Mattermost allows authenticated guest users to enumerate user IDs outside their allowed visibility scope in…lowCVSS 3.1EPSS 0.3%
- CVE-2026-27659: GO-2026-5629 - Mattermost doesn't properly validate CSRF tokens in github.com/mattermost/mattermost-serverlowCVSS 3.1EPSS 0.2%
- CVE-2026-28741: GO-2026-5495 - Mattermost doesn't validate CSRF tokens on an authentication endpoint in…lowCVSS 3.1EPSS 0.2%
- CVE-2026-27656: GO-2026-5360 - Mattermost allows attackers to take over arbitrary user accounts via overly permissive substring matching…lowCVSS 3.1EPSS 0.3%
- CVE-2026-4274: GO-2026-5393 - Mattermost has an Incorrect Authorization issue in github.com/mattermost/mattermost-serverlowCVSS 3.1EPSS 0.2%
- CVE-2026-20719: GO-2026-5245 - Mattermost: Authenticated DoS through failure to prevent rendering of external SVGs on link embeds in…lowCVSS 3.1EPSS 0.4%
- CVE-2026-3108: GO-2026-5067 - Mattermost allows attackers to manipulate administrator terminals via crafted messages containing ANSI and…lowCVSS 3.1EPSS 0.3%
- CVE-2026-3112: GO-2026-5092 - Mattermost allows system administrators to read arbitrary host files via malicious AdvancedLoggingJSON…lowCVSS 3.1EPSS 0.5%
- CVE-2026-7387: Mattermost privilege escalation in group syncable link and patch endpointshighCVSS 8.8EPSS 0.4%
- CVE-2026-7184: Mattermost sensitive information disclosure in Remote Cluster APImediumCVSS 6.5EPSS 0.4%
- CVE-2026-6961: Mattermost path traversal in shared channel file synchighCVSS 7.6EPSS 0.4%
- CVE-2026-6739: Mattermost privilege escalation in role patch APImediumCVSS 6.7EPSS 0.5%
- CVE-2026-6689: Mattermost missing authorization for invite settings during team creationmediumCVSS 4.3EPSS 0.3%
- CVE-2026-6046: Mattermost message interception via predictable bot usernamesmediumCVSS 5.3EPSS 0.3%
- CVE-2026-3433: Mattermost information disclosure in role_updated WebSocket eventsmediumCVSS 4.3EPSS 0.3%
- CVE-2026-4915: Mattermost Server denial of service via null webhook attachmentmediumCVSS 6.5EPSS 0.4%
- CVE-2026-5740: Mattermost Server denial of service via msgpack WebSocket frameshighCVSS 7.5EPSS 0.6%
- CVE-2026-4055: Mattermost incorrect authorization in Playbook run creationmediumCVSS 4.3EPSS 0.3%
- CVE-2026-6346: Mattermost sensitive information disclosure in support packet generationhighCVSS 8.7EPSS 0.4%
- CVE-2026-6345: Mattermost password disclosure in user creationmediumCVSS 6.5EPSS 0.4%
- CVE-2026-6343: Mattermost Incorrect Authorization in Playbooks via /get endpointmediumCVSS 4.3EPSS 0.3%
- CVE-2026-6339: Mattermost origin validation error in burn-on-read reveal endpointmediumCVSS 4.3EPSS 0.2%
- CVE-2026-6333: Mattermost Server SSRF via Host header in slash commandslowCVSS 3.5EPSS 0.2%
- CVE-2026-5163: Mattermost missing authorization in AI-assisted message rewritesmediumCVSS 6.5EPSS 0.3%
Most severe github.com/mattermost/mattermost/server/v8 (Go) vulnerabilities
Exploited in the wild first, then by severity and CVSS score.
- CVE-2026-7387: Mattermost privilege escalation in group syncable link and patch endpointshighCVSS 8.8EPSS 0.4%
- CVE-2026-6346: Mattermost sensitive information disclosure in support packet generationhighCVSS 8.7EPSS 0.4%
- CVE-2026-6961: Mattermost path traversal in shared channel file synchighCVSS 7.6EPSS 0.4%
- CVE-2026-5740: Mattermost Server denial of service via msgpack WebSocket frameshighCVSS 7.5EPSS 0.6%
- CVE-2026-6739: Mattermost privilege escalation in role patch APImediumCVSS 6.7EPSS 0.5%
- CVE-2026-7184: Mattermost sensitive information disclosure in Remote Cluster APImediumCVSS 6.5EPSS 0.4%
- CVE-2026-6345: Mattermost password disclosure in user creationmediumCVSS 6.5EPSS 0.4%
- CVE-2026-4915: Mattermost Server denial of service via null webhook attachmentmediumCVSS 6.5EPSS 0.4%
- CVE-2026-5163: Mattermost missing authorization in AI-assisted message rewritesmediumCVSS 6.5EPSS 0.3%
- CVE-2026-3590: Mattermost has session spoofing due to lack of single-use consumption of guest magic link tokens enforcementmediumCVSS 6.5EPSS 0.2%
Vulnerabilities per week
The last 13 weeks, by the week each vulnerability was published.
| Week of | Bar | Vulns | Critical |
|---|---|---|---|
| 29 Jun 2026 | 0 | 0 | |
| 6 Jul 2026 | 0 | 0 | |
| 13 Jul 2026 | 0 | 0 | |
| 20 Jul 2026 | 0 | 0 | |
| 27 Jul 2026 | 0 | 0 | |
| 3 Aug 2026 | 0 | 0 | |
| 10 Aug 2026 | 0 | 0 | |
| 17 Aug 2026 | 0 | 0 | |
| 24 Aug 2026 | 0 | 0 | |
| 31 Aug 2026 | 0 | 0 | |
| 7 Sep 2026 | 0 | 0 | |
| 14 Sep 2026 | 0 | 0 | |
| 21 Sep 2026 | 0 | 0 |
How this is built
Junglewise Threat Intelligence collects vulnerabilities from NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories, and matches each one to the technologies and vendors it affects. Dates are the date a vulnerability was published, in UTC.
The pages are rebuilt from the database every hour. Frozen weekly and monthly reports never change once published, so they can be cited.
Use this data
The same data is at https://junglewise.ai/threats/technologies/github-com-mattermost-mattermost-server-v8.json, for scripts and language models. It is free to reuse under CC BY 4.0 with a link back to this page.
Cite as: Junglewise Threat Intelligence, "github.com/mattermost/mattermost/server/v8 (Go) vulnerabilities", https://junglewise.ai/threats/technologies/github-com-mattermost-mattermost-server-v8, 27 September 2026.