{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2023-53621 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2023-53621 is a high-severity vulnerability in Linux kernel, published on 7 Oct 2025. 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-2023-53621 and fix it if it is affected.\n\nWhat it is: CVE-2023-53621 is a high-severity vulnerability in Linux kernel, published on 7 Oct 2025. 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-2023-53621 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-2023-53621/ (Markdown: https://insights.sbomify.com/CVE-2023-53621/index.md)","id":"CVE-2023-53621","markdown":"https://insights.sbomify.com/CVE-2023-53621/index.md","name":"CVE-2023-53621","record":{"aliases":["BELL-CVE-2023-53621","DEBIAN-CVE-2023-53621","GHSA-qhmw-vr57-jm8g","UBUNTU-CVE-2023-53621"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A race condition in the Linux kernel memory control subsystem can cause a NULL pointer dereference, leading to a system crash.","user_interaction":"not_required","vuln_class":"null_dereference"},"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-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmemcontrol: ensure memcg acquired by id is properly set up\n\nIn the eviction recency check, we attempt to retrieve the memcg to which\nthe folio belonged when it was evicted, by the memcg id stored in the\nshadow entry.  However, there is a chance that the retrieved memcg is not\nthe original memcg that has been killed, but a new one which happens to\nhave the same id.\n\nThis is a somewhat unfortunate, but acceptable and rare inaccuracy in the\nheuristics.  However, if we retrieve this new memcg between its allocation\nand when it is properly attached to the memcg hierarchy, we could run into\nthe following NULL pointer exception during the memcg hierarchy traversal\ndone in mem_cgroup_get_nr_swap_pages():\n\n[ 155757.793456] BUG: kernel NULL pointer dereference, address: 00000000000000c0\n[ 155757.807568] #PF: supervisor read access in kernel mode\n[ 155757.818024] #PF: error_code(0x0000) - not-present page\n[ 155757.828482] PGD 401f77067 P4D 401f77067 PUD 401f76067 PMD 0\n[ 155757.839985] Oops: 0000 [#1] SMP\n[ 155757.887870] RIP: 0010:mem_cgroup_get_nr_swap_pages+0x3d/0xb0\n[ 155757.899377] Code: 29 19 4a 02 48 39 f9 74 63 48 8b 97 c0 00 00 00 48 8b b7 58 02 00 00 48 2b b7 c0 01 00 00 48 39 f0 48 0f 4d c6 48 39 d1 74 42 \u003c48\u003e 8b b2 c0 00 00 00 48 8b ba 58 02 00 00 48 2b ba c0 01 00 00 48\n[ 155757.937125] RSP: 0018:ffffc9002ecdfbc8 EFLAGS: 00010286\n[ 155757.947755] RAX: 00000000003a3b1c RBX: 000007ffffffffff RCX: ffff888280183000\n[ 155757.962202] RDX: 0000000000000000 RSI: 0007ffffffffffff RDI: ffff888bbc2d1000\n[ 155757.976648] RBP: 0000000000000001 R08: 000000000000000b R09: ffff888ad9cedba0\n[ 155757.991094] R10: ffffea0039c07900 R11: 0000000000000010 R12: ffff888b23a7b000\n[ 155758.005540] R13: 0000000000000000 R14: ffff888bbc2d1000 R15: 000007ffffc71354\n[ 155758.019991] FS:  00007f6234c68640(0000) GS:ffff88903f9c0000(0000) knlGS:0000000000000000\n[ 155758.036356] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 155758.048023] CR2: 00000000000000c0 CR3: 0000000a83eb8004 CR4: 00000000007706e0\n[ 155758.062473] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n[ 155758.076924] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n[ 155758.091376] PKRU: 55555554\n[ 155758.096957] Call Trace:\n[ 155758.102016]  \u003cTASK\u003e\n[ 155758.106502]  ? __die+0x78/0xc0\n[ 155758.112793]  ? page_fault_oops+0x286/0x380\n[ 155758.121175]  ? exc_page_fault+0x5d/0x110\n[ 155758.129209]  ? asm_exc_page_fault+0x22/0x30\n[ 155758.137763]  ? mem_cgroup_get_nr_swap_pages+0x3d/0xb0\n[ 155758.148060]  workingset_test_recent+0xda/0x1b0\n[ 155758.157133]  workingset_refault+0xca/0x1e0\n[ 155758.165508]  filemap_add_folio+0x4d/0x70\n[ 155758.173538]  page_cache_ra_unbounded+0xed/0x190\n[ 155758.182919]  page_cache_sync_ra+0xd6/0x1e0\n[ 155758.191738]  filemap_read+0x68d/0xdf0\n[ 155758.199495]  ? mlx5e_napi_poll+0x123/0x940\n[ 155758.207981]  ? __napi_schedule+0x55/0x90\n[ 155758.216095]  __x64_sys_pread64+0x1d6/0x2c0\n[ 155758.224601]  do_syscall_64+0x3d/0x80\n[ 155758.232058]  entry_SYSCALL_64_after_hwframe+0x46/0xb0\n[ 155758.242473] RIP: 0033:0x7f62c29153b5\n[ 155758.249938] Code: e8 48 89 75 f0 89 7d f8 48 89 4d e0 e8 b4 e6 f7 ff 41 89 c0 4c 8b 55 e0 48 8b 55 e8 48 8b 75 f0 8b 7d f8 b8 11 00 00 00 0f 05 \u003c48\u003e 3d 00 f0 ff ff 77 33 44 89 c7 48 89 45 f8 e8 e7 e6 f7 ff 48 8b\n[ 155758.288005] RSP: 002b:00007f6234c5ffd0 EFLAGS: 00000293 ORIG_RAX: 0000000000000011\n[ 155758.303474] RAX: ffffffffffffffda RBX: 00007f628c4e70c0 RCX: 00007f62c29153b5\n[ 155758.318075] RDX: 000000000003c041 RSI: 00007f61d2986000 RDI: 0000000000000076\n[ 155758.332678] RBP: 00007f6234c5fff0 R08: 0000000000000000 R09: 0000000064d5230c\n[ 155758.347452] R10: 000000000027d450 R11: 0000000000000293 R12: 000000000003c041\n[ 155758.362044] R13: 00007f61d2986000 R14: 00007f629e11b060 R15: 000000000027d450\n[ 155758.376661]  \u003c/TASK\u003e\n\nThis patch fixes the issue by moving the memcg's id publication from the\nalloc stage to \n---truncated---","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":"memcontrol: ensure memcg acquired by id is properly set up","id":"CVE-2023-53621","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2023"},"n_packages":0,"n_references":2,"next":{"headline":"gfs2: Fix possible data races in gfs2_show_options()","id":"CVE-2023-53622"},"packages":[],"prev":{"headline":"md: fix soft lockup in status_resync","id":"CVE-2023-53620"},"products":["Linux"],"published":"2025-10-07","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":"2026-05-11","vendors":["Linux"]},"summary":"A race condition in the Linux kernel memory control subsystem can cause a NULL pointer dereference, leading to a system crash.","url":"https://insights.sbomify.com/CVE-2023-53621/"}