{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-93253 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-93253 is an use after free vulnerability in Linux, published on 24 Sep 2026."},"fix_prompt":"Check this codebase for CVE-2026-93253 and fix it if it is affected.\n\nWhat it is: CVE-2026-93253 is an use after free vulnerability in Linux, published on 24 Sep 2026. \nExploitation: There is no known exploitation of CVE-2026-93253 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-2026-93253/ (Markdown: https://insights.sbomify.com/CVE-2026-93253/index.md)","id":"CVE-2026-93253","markdown":"https://insights.sbomify.com/CVE-2026-93253/index.md","name":"CVE-2026-93253","record":{"aliases":["DEBIAN-CVE-2026-93253","GHSA-w946-9g6f-2799","UBUNTU-CVE-2026-93253"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"unknown","non_default_config":true,"product_category":"Linux kernel","requires_auth":"none","summary":"A use-after-free vulnerability in the Linux kernel scheduler isolation code can cause a kernel warning or crash during boot when specific parameters are used.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched/isolation: Defer freeing of cpumask memblock memory to initcall\n\nWhen testing a linux-next kernel with commit 59bd1d914bb5 (\"memblock:\nwarn when freeing reserved memory before memory map is initialized\"),\nthe following warning was hit when there was a \"nohz_full\" kernel boot\nparameter.\n\n  Cannot free reserved memory because of deferred initialization of the memory map\n  WARNING: mm/memblock.c:904 at __free_reserved_area+0xde/0xf0, CPU#0: swapper/0/0\n    :\n  Call Trace:\n   \u003cTASK\u003e\n   memblock_phys_free+0xcb/0x100\n   housekeeping_init+0x14c/0x170\n   start_kernel+0x207/0x450\n   x86_64_start_reservations+0x24/0x30\n   x86_64_start_kernel+0xda/0xe0\n   common_startup_64+0x13e/0x141\n   \u003c/TASK\u003e\n\nIOW, we shouldn't free memblock allocated memory so early\nin the boot process when memory map isn't fully initialized in\ndeferred_init_memmap().\n\nFix it by saving the housekeeping cpumask memblock memory to be\nfreed into a llist free list in housekeeping_init() and add a new\nhousekeeping_late_init() helper to defer the actual freeing of memblock\nmemory to when initcall's are being processed. The cpumask memblock\nmemory is treated as a llist_node with the size of a \"long\" type which\nis also smallest cpumask size that can be allocated.\n\nThe non-atomic version of the llist APIs are used as there is no\ncontention.\n\nThis commit depends on the presence of commit 7c2eee9c1367 (\"memblock:\ndon't touch memblock arrays when memblock_free() is called late\")\nto prevent a KASAN UAF bug report [1].\n\n [1] https://lore.kernel.org/lkml/20260505051821.1107133-1-longman@redhat.com/","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":"sched/isolation: Defer freeing of cpumask memblock memory to initcall","id":"CVE-2026-93253","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"use_after_free","year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"arm64: entry: Avoid unnecessary local_irq_disable() on kernel exit","id":"CVE-2026-93254"},"packages":[],"prev":{"headline":"ocfs2: fix circular locking dependency in ocfs2_init_acl()","id":"CVE-2026-93252"},"products":["Linux"],"published":"2026-09-24","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"A use-after-free vulnerability in the Linux kernel scheduler isolation code can cause a kernel warning or crash during boot when specific parameters are used.","url":"https://insights.sbomify.com/CVE-2026-93253/"}