{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-9571 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-9571 is a medium-severity authentication bypass vulnerability in Mattermost Mattermost Server, published on 13 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-9571 and fix it if it is affected.\n\nWhat it is: CVE-2026-9571 is a medium-severity authentication bypass vulnerability in Mattermost Mattermost Server, published on 13 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-9571 in the wild and no public exploit code.\n\nAffected product: Mattermost Mattermost Server. No package-level version data is available, so check the vendor advisory linked from the reference page.\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-2026-9571/ (Markdown: https://insights.sbomify.com/CVE-2026-9571/index.md)","id":"CVE-2026-9571","markdown":"https://insights.sbomify.com/CVE-2026-9571/index.md","name":"CVE-2026-9571","record":{"aliases":["GHSA-4v7j-4mvr-5975","MINI-3xgw-xw35-68pj","MINI-62q2-848r-5hmw"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["account_takeover","security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"Mattermost collaboration platform","requires_auth":"high_privilege","summary":"Deactivated users or attackers with refresh tokens can obtain valid access tokens, bypassing account deactivation controls in Mattermost.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Mattermost","cpe":[{"product":"mattermost_server","vendor":"mattermost"}],"cvss":{"score":5.9,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-305","name":"Authentication Bypass by Primary Weakness"}],"description":"Mattermost versions 11.7.x \u003c= 11.7.2, 11.6.x \u003c= 11.6.4, 10.11.x \u003c= 10.11.19 fail to invalidate OAuth refresh tokens upon user account deactivation, which allows a deactivated user or an attacker in possession of a valid refresh token to obtain new functional access tokens via the OAuth refresh token grant endpoint.. Mattermost Advisory ID: MMSA-2026-00680","ecosystems":[],"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":"Deactivated user accounts can continue to obtain valid OAuth access tokens via refresh token grant in Mattermost","id":"CVE-2026-9571","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"mattermost:mattermost_server","products":["mattermost:mattermost_server"],"type":"auth_bypass","year":"2026"},"n_packages":0,"n_references":1,"next":{"headline":"GPAC MP4Box media.c Media_GetSample memory leak","id":"CVE-2026-9572"},"packages":[],"prev":{"headline":"Taskbuilder \u003c 5.0.8 - Reflected XSS via Shortcode","id":"CVE-2026-9570"},"products":["Mattermost"],"published":"2026-07-13","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":"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":"2026-07-15","vendors":["Mattermost"]},"summary":"Deactivated users or attackers with refresh tokens can obtain valid access tokens, bypassing account deactivation controls in Mattermost.","url":"https://insights.sbomify.com/CVE-2026-9571/"}