GO-2026-5671

See a problem?
Please try reporting it to the source first.
Source
https://pkg.go.dev/vuln/GO-2026-5671
Import Source
https://vuln.go.dev/ID/GO-2026-5671.json
JSON Data
https://api.osv.dev/v1/vulns/GO-2026-5671
Aliases
Published
2026-06-25T22:34:38Z
Modified
2026-06-25T23:01:38.693940001Z
Summary
Mattermost doesn't validate the Host header when constructing response URLs for custom slash command in github.com/mattermost/mattermost-server
Details

Mattermost doesn't validate the Host header when constructing response URLs for custom slash command 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/v5 before v5.3.2-0.20260325160634-e738016c5920.

Database specific 
{
    "url": "https://pkg.go.dev/vuln/GO-2026-5671",
    "review_status": "UNREVIEWED"
}
References

Affected packages

Go
github.com/mattermost/mattermost-server

Package

Name
github.com/mattermost/mattermost-server
View open source insights on deps.dev
Purl
pkg:golang/github.com/mattermost/mattermost-server

Affected ranges

Type
SEMVER
Events
Introduced
10.11.0+incompatible
Fixed
10.11.14+incompatible
Introduced
11.5.0+incompatible
Fixed
11.5.2+incompatible

Database specific

source 
"https://vuln.go.dev/ID/GO-2026-5671.json"
github.com/mattermost/mattermost-server/v5

Package

Name
github.com/mattermost/mattermost-server/v5
View open source insights on deps.dev
Purl
pkg:golang/github.com/mattermost/mattermost-server/v5

Affected ranges

Type
SEMVER
Events
Introduced
0Unknown introduced version / All previous versions are affected

Ecosystem specific 

{
    "custom_ranges": [
        {
            "events": [
                {
                    "introduced": "0"
                },
                {
                    "fixed": "5.3.2-0.20260325160634-e738016c5920"
                }
            ],
            "type": "ECOSYSTEM"
        }
    ]
}

Database specific

source 
"https://vuln.go.dev/ID/GO-2026-5671.json"
github.com/mattermost/mattermost-server/v6

Package

Name
github.com/mattermost/mattermost-server/v6
View open source insights on deps.dev
Purl
pkg:golang/github.com/mattermost/mattermost-server/v6

Affected ranges

Type
SEMVER
Events
Introduced
0Unknown introduced version / All previous versions are affected

Database specific

source 
"https://vuln.go.dev/ID/GO-2026-5671.json"
github.com/mattermost/mattermost/server/v8

Package

Name
github.com/mattermost/mattermost/server/v8
View open source insights on deps.dev
Purl
pkg:golang/github.com/mattermost/mattermost/server/v8

Affected ranges

Type
SEMVER
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
8.0.0-20260325160634-e738016c5920

Database specific

source 
"https://vuln.go.dev/ID/GO-2026-5671.json"