{"cve":"CVE-2026-27769","nvd":{"published":"2026-04-15T11:16:33.017","modified":"2026-06-17T10:27:39.680","status":"Analyzed","description":"Mattermost versions 10.11.x <= 10.11.12 fail to validate whether users were correctly owned by the correct Connected Workspace which allows a malicious remote server connected using the Conntexted Workspaces feature to change the displayed status of local users via the Connected Workspaces API.. Mattermost Advisory ID: MMSA-2026-00603","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N","score":2.7},"cwes":["CWE-862"],"references":["https://mattermost.com/security-updates"],"products":["mattermost:mattermost_server"],"source":"nvd","synced_at":"2026-10-19T22:30:49.762551342+00:00"},"epss":{"cve":"CVE-2026-27769","score":0.00167,"percentile":0.05955,"date":"2026-11-01"},"kev":null,"osv":[{"id":"GHSA-mxxh-fmjq-j6x4","url":"https://osv.dev/vulnerability/GHSA-mxxh-fmjq-j6x4","summary":"Mattermost doesn't validate whether users were correctly owned by the correct Connected Workspace","modified":"2026-06-25T23:11:32.697672257Z","packages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","purl":"pkg:golang/github.com/mattermost/mattermost-server","ranges":[">=8.0.0-20250721062209-4952acea88ce <8.0.0-20260316060126-bc1a2b34b1f9"],"fixed":["8.0.0-20260316060126-bc1a2b34b1f9"]}]},{"id":"GO-2026-5522","url":"https://osv.dev/vulnerability/GO-2026-5522","summary":"Mattermost doesn't validate whether users were correctly owned by the correct Connected Workspace in github.com/mattermost/mattermost-server","modified":"2026-06-25T23:01:31.638503820Z","packages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","purl":"pkg:golang/github.com/mattermost/mattermost-server","ranges":["all versions"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}