{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-64239 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-64239 is a high-severity use after free vulnerability in Linux kernel, published on 24 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-64239 and fix it if it is affected.\n\nWhat it is: CVE-2026-64239 is a high-severity use after free vulnerability in Linux kernel, published on 24 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-64239 in the wild and no public exploit code.\n\nAffected product: Linux kernel. 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-2026-64239/ (Markdown: https://insights.sbomify.com/CVE-2026-64239/index.md)","id":"CVE-2026-64239","markdown":"https://insights.sbomify.com/CVE-2026-64239/index.md","name":"CVE-2026-64239","record":{"aliases":["BELL-CVE-2026-64239","DEBIAN-CVE-2026-64239","GHSA-v8wj-8j36-23j2","ROOT-OS-UBUNTU-2204-CVE-2026-64239","UBUNTU-CVE-2026-64239"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["code_execution","privilege_escalation"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A use-after-free in the Linux kernel DAMON sysfs interface allows local attackers to potentially execute code or escalate privileges when debug kobject release is enabled.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":7.8,"severity":"high","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-416","name":"Use After Free"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/damon/sysfs-schemes: delete tried region in regions_rmdirs()\n\nDAMON sysfs maintains the DAMOS tried region directory objects via a\nlinked list.  When the user requests refresh of the directories, DAMON\nsysfs removes all the region directories first, and then generate updated\nregions directory on the empty space.  The removal function\n(damon_sysfs_scheme_regions_rm_dirs()) only puts the kobj objects. \nDeletion of the container region object from the linked list is done\ninside the kobj release callback function.\n\nIf somehow the callback invocation is delayed, the list will contain\nregions list that gonna be freed.  If the updated region directories\ncreation is started in this situation, the list can be corrupted and\nuse-after-free can happen.\n\nBecause the kobj objects are managed by only DAMON sysfs, the issue cannot\nhappen in normal situation.  But, such delays can be made on kernels that\nbuilt with CONFIG_DEBUG_KOBJECT_RELEASE.  On the kernel, the issue can\nindeed be reproduced like below.\n\n    # damo start --damos_action stat\n    # cd /sys/kernel/mm/damon/admin/kdamonds/0/\n    # for i in {1..10}; do echo update_schemes_tried_regions \u003e state; done\n    # dmesg | grep underflow\n    [   89.296152] refcount_t: underflow; use-after-free.\n\nFix the issue by removing the region object from the list when\ndecrementing the reference count.\n\nAlso update damos_sysfs_populate_region_dir() to add the region object to\nthe list only after the kobject_init_and_add() is success, so that fail of\nkobject_init_and_add() is not leaving the deallocated object on the list.\n\nThe issue was discovered [1] by Sashiko.","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":"mm/damon/sysfs-schemes: delete tried region in regions_rmdirs()","id":"CVE-2026-64239","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"use_after_free","year":"2026"},"n_packages":0,"n_references":5,"next":{"headline":"media: rc: igorplugusb: fix control request setup packet","id":"CVE-2026-64240"},"packages":[],"prev":{"headline":"gpio: shared: fix deadlock on shared proxy's parent removal","id":"CVE-2026-64238"},"products":["Linux"],"published":"2026-07-24","related":[{"cvss_score":8.8,"headline":"Linux Kernel Out-of-Bounds Write","id":"CVE-2026-53266","kev_date_added":"2026-09-18","published":"2026-06-25"},{"cvss_score":8.8,"headline":"Linux Kernel Improper Input Validation","id":"CVE-2013-6282","kev_date_added":"2022-09-15","published":"2013-11-19"},{"cvss_score":8.4,"headline":"Linux Kernel Heap-Based Buffer Overflow","id":"CVE-2022-0185","kev_date_added":"2024-08-21","published":"2022-02-11"},{"cvss_score":8.4,"headline":"Linux Kernel Privilege Escalation","id":"CVE-2013-2094","kev_date_added":"2022-09-15","published":"2013-05-14"},{"cvss_score":7.8,"headline":"Linux Kernel Unspecified","id":"CVE-2026-53362","kev_date_added":"2026-08-27","published":"2026-07-04"},{"cvss_score":7.8,"headline":"Linux Kernel Missing Initialization of a Variable","id":"CVE-2026-46300","kev_date_added":"2026-10-28","published":"2026-05-23"},{"cvss_score":7.8,"headline":"Linux Kernel Race Condition","id":"CVE-2025-39964","kev_date_added":"2026-09-18","published":"2025-10-13"}],"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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-07-24","vendors":["Linux"]},"summary":"A use-after-free in the Linux kernel DAMON sysfs interface allows local attackers to potentially execute code or escalate privileges when debug kobject release is enabled.","url":"https://insights.sbomify.com/CVE-2026-64239/"}