{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2023-53642 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2023-53642 is a medium-severity denial of service 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-2023-53642 and fix it if it is affected.\n\nWhat it is: CVE-2023-53642 is a medium-severity denial of service 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-2023-53642 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-2023-53642/ (Markdown: https://insights.sbomify.com/CVE-2023-53642/index.md)","id":"CVE-2023-53642","markdown":"https://insights.sbomify.com/CVE-2023-53642/index.md","name":"CVE-2023-53642","record":{"aliases":["BELL-CVE-2023-53642","DEBIAN-CVE-2023-53642","GHSA-h9cf-c7q8-gcqh","ROOT-OS-UBUNTU-2404-CVE-2023-53642","UBUNTU-CVE-2023-53642"],"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 kernel exception handling bug causes a system crash instead of an error when clearing user memory, leading to denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86: fix clear_user_rep_good() exception handling annotation\n\nThis code no longer exists in mainline, because it was removed in\ncommit d2c95f9d6802 (\"x86: don't use REP_GOOD or ERMS for user memory\nclearing\") upstream.\n\nHowever, rather than backport the full range of x86 memory clearing and\ncopying cleanups, fix the exception table annotation placement for the\nfinal 'rep movsb' in clear_user_rep_good(): rather than pointing at the\nactual instruction that did the user space access, it pointed to the\nregister move just before it.\n\nThat made sense from a code flow standpoint, but not from an actual\nusage standpoint: it means that if user access takes an exception, the\nexception handler won't actually find the instruction in the exception\ntables.\n\nAs a result, rather than fixing it up and returning -EFAULT, it would\nthen turn it into a kernel oops report instead, something like:\n\n    BUG: unable to handle page fault for address: 0000000020081000\n    #PF: supervisor write access in kernel mode\n    #PF: error_code(0x0002) - not-present page\n    ...\n    RIP: 0010:clear_user_rep_good+0x1c/0x30 arch/x86/lib/clear_page_64.S:147\n    ...\n    Call Trace:\n      __clear_user arch/x86/include/asm/uaccess_64.h:103 [inline]\n      clear_user arch/x86/include/asm/uaccess_64.h:124 [inline]\n      iov_iter_zero+0x709/0x1290 lib/iov_iter.c:800\n      iomap_dio_hole_iter fs/iomap/direct-io.c:389 [inline]\n      iomap_dio_iter fs/iomap/direct-io.c:440 [inline]\n      __iomap_dio_rw+0xe3d/0x1cd0 fs/iomap/direct-io.c:601\n      iomap_dio_rw+0x40/0xa0 fs/iomap/direct-io.c:689\n      ext4_dio_read_iter fs/ext4/file.c:94 [inline]\n      ext4_file_read_iter+0x4be/0x690 fs/ext4/file.c:145\n      call_read_iter include/linux/fs.h:2183 [inline]\n      do_iter_readv_writev+0x2e0/0x3b0 fs/read_write.c:733\n      do_iter_read+0x2f2/0x750 fs/read_write.c:796\n      vfs_readv+0xe5/0x150 fs/read_write.c:916\n      do_preadv+0x1b6/0x270 fs/read_write.c:1008\n      __do_sys_preadv2 fs/read_write.c:1070 [inline]\n      __se_sys_preadv2 fs/read_write.c:1061 [inline]\n      __x64_sys_preadv2+0xef/0x150 fs/read_write.c:1061\n      do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n      do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80\n      entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nwhich then looks like a filesystem bug rather than the incorrect\nexception annotation that it is.\n\n[ The alternative to this one-liner fix is to take the upstream series\n  that cleans this all up:\n\n    68674f94ffc9 (\"x86: don't use REP_GOOD or ERMS for small memory copies\")\n    20f3337d350c (\"x86: don't use REP_GOOD or ERMS for small memory clearing\")\n    adfcf4231b8c (\"x86: don't use REP_GOOD or ERMS for user memory copies\")\n  * d2c95f9d6802 (\"x86: don't use REP_GOOD or ERMS for user memory clearing\")\n    3639a535587d (\"x86: move stac/clac from user copy routines into callers\")\n    577e6a7fd50d (\"x86: inline the 'rep movs' in user copies for the FSRM case\")\n    8c9b6a88b7e2 (\"x86: improve on the non-rep 'clear_user' function\")\n    427fda2c8a49 (\"x86: improve on the non-rep 'copy_user' function\")\n  * e046fe5a36a9 (\"x86: set FSRS automatically on AMD CPUs that have FSRM\")\n    e1f2750edc4a (\"x86: remove 'zerorest' argument from __copy_user_nocache()\")\n    034ff37d3407 (\"x86: rewrite '__copy_user_nocache' function\")\n\n  with either the whole series or at a minimum the two marked commits\n  being needed to fix this issue ]","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":"x86: fix clear_user_rep_good() exception handling annotation","id":"CVE-2023-53642","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"denial_of_service","year":"2023"},"n_packages":0,"n_references":4,"next":{"headline":"nvme-tcp: don't access released socket during error recovery","id":"CVE-2023-53643"},"packages":[],"prev":{"headline":"wifi: ath9k: hif_usb: fix memory leak of remain_skbs","id":"CVE-2023-53641"},"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":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A kernel exception handling bug causes a system crash instead of an error when clearing user memory, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2023-53642/"}