{"cve":"CVE-2026-4635","nvd":{"published":"2026-05-22T11:16:22.747","modified":"2026-07-23T16:10:00.137","status":"Analyzed","description":"Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to archive the channel before removing persistent notifications which allows authenticated user to crash the server via timing the creation of persistent notification message between the server deleting existing persistent notifications and archiving the channel.. Mattermost Advisory ID: MMSA-2026-00637","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.3},"cwes":["CWE-362"],"references":["https://mattermost.com/security-updates"],"products":["mattermost:mattermost_server"],"source":"nvd","synced_at":"2026-10-19T22:36:28.938604137+00:00"},"epss":{"cve":"CVE-2026-4635","score":0.00172,"percentile":0.06583,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-pg7c-462j-grxv","url":"https://osv.dev/vulnerability/GHSA-pg7c-462j-grxv","summary":"Mattermost doesn't archive the channel before removing persistent notifications","modified":"2026-07-07T16:11:32.973521518Z","packages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","purl":"pkg:golang/github.com/mattermost/mattermost-server","ranges":[">=11.6.0 <11.6.1"],"fixed":["11.6.1"]},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","purl":"pkg:golang/github.com/mattermost/mattermost-server","ranges":[">=11.5.0 <11.5.4"],"fixed":["11.5.4"]},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","purl":"pkg:golang/github.com/mattermost/mattermost-server","ranges":[">=11.4.0 <11.4.5"],"fixed":["11.4.5"]},{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","purl":"pkg:golang/github.com/mattermost/mattermost-server","ranges":[">=10.11.0 <10.11.15"],"fixed":["10.11.15"]}]},{"id":"GO-2026-5820","url":"https://osv.dev/vulnerability/GO-2026-5820","summary":"Mattermost doesn't archive the channel before removing persistent notifications in github.com/mattermost/mattermost-server","modified":"2026-07-07T16:01:34.910029874Z","packages":[{"ecosystem":"Go","name":"github.com/mattermost/mattermost-server","purl":"pkg:golang/github.com/mattermost/mattermost-server","ranges":[">=10.11.0+incompatible <10.11.15+incompatible",">=11.4.0+incompatible <11.4.5+incompatible",">=11.5.0+incompatible <11.5.4+incompatible",">=11.6.0+incompatible <11.6.1+incompatible"],"fixed":["10.11.15+incompatible","11.4.5+incompatible","11.5.4+incompatible","11.6.1+incompatible"]}]}],"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."]}