{"answers":{"affected":"14 open source packages ship an affected version, including github.com/mattermost/mattermost/server/v8, github.com/mattermost/mattermost-server and github.com/mattermost/mattermost-server/v5. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-6346 in the wild and no public exploit code.","fix":"Upgrade github.com/mattermost/mattermost/server/v8 to a fixed version for your release line: 8.0.0-20260326202606-fac92f4a71f3, 10.11.14, 11.4.4 or 11.5.2.","what":"CVE-2026-6346 is a high-severity vulnerability in Mattermost Mattermost Server, published on 18 May 2026. An attacker needs administrator access to exploit it, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-6346 and fix it if it is affected.\n\nWhat it is: CVE-2026-6346 is a high-severity vulnerability in Mattermost Mattermost Server, published on 18 May 2026. An attacker needs administrator access to exploit it, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-6346 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- github.com/mattermost/mattermost/server/v8 (Go): affected all versions; fixed in 8.0.0-20260326202606-fac92f4a71f3\n- github.com/mattermost/mattermost/server/v8 (Go): affected all versions; fixed in 8.0.0-20260326202606-fac92f4a71f3\n- github.com/mattermost/mattermost/server/v8 (Go): affected all versions; fixed in 8.0.0-20260326202606-fac92f4a71f3\n- github.com/mattermost/mattermost/server/v8 (Go): affected from 10.11.0; fixed in 10.11.14\n- github.com/mattermost/mattermost/server/v8 (Go): affected from 10.11.0; fixed in 10.11.14\n- github.com/mattermost/mattermost/server/v8 (Go): affected from 11.4.0; fixed in 11.4.4\n- github.com/mattermost/mattermost/server/v8 (Go): affected from 11.4.0; fixed in 11.4.4\n- github.com/mattermost/mattermost/server/v8 (Go): affected from 11.5.0; fixed in 11.5.2\n- github.com/mattermost/mattermost/server/v8 (Go): affected from 11.5.0; fixed in 11.5.2\n- github.com/mattermost/mattermost-server (Go): affected all versions; fixed in 5.3.2-0.20260326202606-fac92f4a71f3\n- github.com/mattermost/mattermost-server (Go): affected all versions; fixed in 5.3.2-0.20260326202606-fac92f4a71f3\n- github.com/mattermost/mattermost-server (Go): affected from 10.11.0+incompatible; fixed in 10.11.14+incompatible, 11.4.4+incompatible, 11.5.2+incompatible\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-6346/ (Markdown: https://insights.sbomify.com/CVE-2026-6346/index.md)","id":"CVE-2026-6346","markdown":"https://insights.sbomify.com/CVE-2026-6346/index.md","name":"CVE-2026-6346","record":{"aliases":["GHSA-9p64-jpc7-m2rp","GO-2026-5293"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["data_read"],"network_reachable":"yes","non_default_config":false,"product_category":"Mattermost collaboration platform","requires_auth":"high_privilege","summary":"Attackers with access to support packets can obtain sensitive credentials in plaintext due to insufficient sanitization of configuration fields.","user_interaction":"not_required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Mattermost","cpe":[{"product":"mattermost_server","vendor":"mattermost"}],"cvss":{"score":8.7,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-200","name":"Exposure of Sensitive Information to an Unauthorized Actor"}],"description":"Mattermost versions 11.5.x \u003c= 11.5.1, 10.11.x \u003c= 10.11.13, 11.4.x \u003c= 11.4.3 fail to sanitize sensitive configuration fields before including them in support packet generation, which allows a Mattermost System Admin or any party with access to a support packet to obtain sensitive credentials in plaintext via downloading a support packet from the System Console.. Mattermost Advisory ID: MMSA-2026-00607","ecosystems":["Go"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Sensitive credentials exposed in plaintext in Mattermost support packets","id":"CVE-2026-6346","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Go","product":"mattermost:mattermost_server","products":["mattermost:mattermost_server"],"type":"information_disclosure","year":"2026"},"n_packages":14,"n_references":1,"next":{"headline":"Mattermost Calls plugin exposes TURN server credentials in plaintext in support packets","id":"CVE-2026-6347"},"packages":[{"ecosystem":"Go","fixed":["5.3.2-0.20260326202606-fac92f4a71f3"],"introduced":["0"],"last_affected":[],"package":"github.com/mattermost/mattermost-server","purl":null,"source":"GHSA-9p64-jpc7-m2rp"},{"ecosystem":"Go","fixed":["5.3.2-0.20260326202606-fac92f4a71f3"],"introduced":["0"],"last_affected":[],"package":"github.com/mattermost/mattermost-server","purl":"pkg:golang/github.com/mattermost/mattermost-server","source":"GHSA-9p64-jpc7-m2rp"},{"ecosystem":"Go","fixed":["10.11.14+incompatible","11.4.4+incompatible","11.5.2+incompatible"],"introduced":["10.11.0+incompatible","11.4.0+incompatible","11.5.0+incompatible"],"last_affected":[],"package":"github.com/mattermost/mattermost-server","purl":"pkg:golang/github.com/mattermost/mattermost-server","source":"GO-2026-5293"},{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":[],"package":"github.com/mattermost/mattermost-server/v5","purl":"pkg:golang/github.com/mattermost/mattermost-server/v5","source":"GO-2026-5293"},{"ecosystem":"Go","fixed":[],"introduced":["0"],"last_affected":[],"package":"github.com/mattermost/mattermost-server/v6","purl":"pkg:golang/github.com/mattermost/mattermost-server/v6","source":"GO-2026-5293"},{"ecosystem":"Go","fixed":["8.0.0-20260326202606-fac92f4a71f3"],"introduced":["0"],"last_affected":[],"package":"github.com/mattermost/mattermost/server/v8","purl":null,"source":"GHSA-9p64-jpc7-m2rp"},{"ecosystem":"Go","fixed":["8.0.0-20260326202606-fac92f4a71f3"],"introduced":["0"],"last_affected":[],"package":"github.com/mattermost/mattermost/server/v8","purl":"pkg:golang/github.com/mattermost/mattermost/server/v8","source":"GHSA-9p64-jpc7-m2rp"},{"ecosystem":"Go","fixed":["8.0.0-20260326202606-fac92f4a71f3"],"introduced":["0"],"last_affected":[],"package":"github.com/mattermost/mattermost/server/v8","purl":"pkg:golang/github.com/mattermost/mattermost/server/v8","source":"GO-2026-5293"},{"ecosystem":"Go","fixed":["10.11.14"],"introduced":["10.11.0"],"last_affected":[],"package":"github.com/mattermost/mattermost/server/v8","purl":null,"source":"GHSA-9p64-jpc7-m2rp"},{"ecosystem":"Go","fixed":["10.11.14"],"introduced":["10.11.0"],"last_affected":[],"package":"github.com/mattermost/mattermost/server/v8","purl":"pkg:golang/github.com/mattermost/mattermost/server/v8","source":"GHSA-9p64-jpc7-m2rp"},{"ecosystem":"Go","fixed":["11.4.4"],"introduced":["11.4.0"],"last_affected":[],"package":"github.com/mattermost/mattermost/server/v8","purl":null,"source":"GHSA-9p64-jpc7-m2rp"},{"ecosystem":"Go","fixed":["11.4.4"],"introduced":["11.4.0"],"last_affected":[],"package":"github.com/mattermost/mattermost/server/v8","purl":"pkg:golang/github.com/mattermost/mattermost/server/v8","source":"GHSA-9p64-jpc7-m2rp"},{"ecosystem":"Go","fixed":["11.5.2"],"introduced":["11.5.0"],"last_affected":[],"package":"github.com/mattermost/mattermost/server/v8","purl":null,"source":"GHSA-9p64-jpc7-m2rp"},{"ecosystem":"Go","fixed":["11.5.2"],"introduced":["11.5.0"],"last_affected":[],"package":"github.com/mattermost/mattermost/server/v8","purl":"pkg:golang/github.com/mattermost/mattermost/server/v8","source":"GHSA-9p64-jpc7-m2rp"}],"prev":{"headline":"Prevent password disclosure and force reset during Slack import","id":"CVE-2026-6345"},"products":["Mattermost"],"published":"2026-05-18","related":[{"cvss_score":9.9,"headline":"Account takeover on OAuth/OpenID-enabled servers","id":"CVE-2025-12419","kev_date_added":null,"published":"2025-11-27"},{"cvss_score":9.9,"headline":"Account Takeover via Code Exchange Endpoint","id":"CVE-2025-12421","kev_date_added":null,"published":"2025-11-27"},{"cvss_score":9.9,"headline":"Path Traversal Leading to RCE by Any Authenticated Mattermost User","id":"CVE-2025-4981","kev_date_added":null,"published":"2025-06-20"},{"cvss_score":9.9,"headline":"Arbitrary file read via block duplication in Mattermost Boards","id":"CVE-2025-20051","kev_date_added":null,"published":"2025-02-24"},{"cvss_score":9.9,"headline":"Arbitrary file read in Mattermost Boards via import \u0026 export board archive","id":"CVE-2025-25279","kev_date_added":null,"published":"2025-02-24"},{"cvss_score":9.8,"headline":"Mattermost Server: Insufficient Password-Reset Link Invalidation","id":"CVE-2016-11074","kev_date_added":null,"published":"2020-06-19"},{"cvss_score":9.8,"headline":"Mattermost Server allows attackers to gain privileges by accessing unintended API endpoints with users' credentials","id":"CVE-2017-18885","kev_date_added":null,"published":"2020-06-19"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"Go Vulnerability Database","prefix":"GO"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-05-18","vendors":["Mattermost"]},"summary":"Attackers with access to support packets can obtain sensitive credentials in plaintext due to insufficient sanitization of configuration fields.","url":"https://insights.sbomify.com/CVE-2026-6346/"}