{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-89788 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-89788 is a critical use after free vulnerability in Linux, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-89788 and fix it if it is affected.\n\nWhat it is: CVE-2026-89788 is a critical use after free vulnerability in Linux, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-89788 in the wild and no public exploit code.\n\nAffected product: Linux. 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-2026-89788/ (Markdown: https://insights.sbomify.com/CVE-2026-89788/index.md)","id":"CVE-2026-89788","markdown":"https://insights.sbomify.com/CVE-2026-89788/index.md","name":"CVE-2026-89788","record":{"aliases":["AZL-101159","BELL-CVE-2026-89788","DEBIAN-CVE-2026-89788","GHSA-29wc-2986-775f","UBUNTU-CVE-2026-89788"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["code_execution","privilege_escalation"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel ksmbd","requires_auth":"none","summary":"A race condition in the Linux kernel's ksmbd server allows a use-after-free, potentially enabling local attackers to execute code or escalate privileges.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":9.8,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix tree connection use-after-free in smb2_tree_connect()\n\nksmbd_tree_conn_connect() publishes a new tree connection in\nsess-\u003etree_conns with a single reference and returns its pointer to\nsmb2_tree_connect(). The handler continues to initialize the object and\nbuild the response after publication. A concurrent session logoff can\nerase the connection and drop that reference, freeing the object while\nthe handler still uses it.\n\nBUG: KASAN: slab-use-after-free in smb2_tree_connect+0xe3d/0xf90\n  smb2_tree_connect (fs/smb/server/smb2pdu.c:2872)\n  handle_ksmbd_work\n  process_one_work\n  worker_thread\n  kthread\n\nAfter xa_store() succeeds, take a second reference before releasing\ntree_conns_lock. The original reference belongs to the xarray entry and\nthe second belongs to the creating smb2_tree_connect() handler.\n\nKeep the references balanced in every path:\n\n- On normal exit or an error after publication, smb2_tree_connect()\n  drops its creator reference. Error cleanup also calls\n  ksmbd_tree_conn_disconnect(), which drops the xarray reference only if\n  it removes the exact entry.\n- SMB2 TREE_DISCONNECT uses the same helper to remove the entry and drop\n  its xarray reference. The request's existing lookup reference remains\n  owned by the request and is released by the existing cleanup.\n- Session LOGOFF removes each entry and drops its xarray reference. If\n  it wins the race, later cleanup sees that the entry is gone and does\n  not drop that reference again.\n\nTo enforce this ownership, claim the disconnected state and erase the\nexact entry atomically under tree_conns_lock. This guarantees one drop\nfor the xarray reference and one drop by each in-flight user, regardless\nof which teardown path wins. If logoff removes the entry before\ninitialization completes, fail the connect instead of marking the\ndetached object TREE_CONNECTED.","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":"ksmbd: fix tree connection use-after-free in smb2_tree_connect()","id":"CVE-2026-89788","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"use_after_free","year":"2026"},"n_packages":0,"n_references":4,"next":{"headline":"gtp: add synchronize_net() in gtp_newlink() error path to prevent use-after-free","id":"CVE-2026-89789"},"packages":[],"prev":{"headline":"ext4: check dir entry fits before reading the hash trailer in ext4_search_dir()","id":"CVE-2026-89787"},"products":["Linux"],"published":"2026-09-16","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-21","vendors":["Linux"]},"summary":"A race condition in the Linux kernel's ksmbd server allows a use-after-free, potentially enabling local attackers to execute code or escalate privileges.","url":"https://insights.sbomify.com/CVE-2026-89788/"}