{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2023-52894 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2023-52894 is a medium-severity vulnerability in Linux kernel, published on 21 Aug 2024. 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-2023-52894 and fix it if it is affected.\n\nWhat it is: CVE-2023-52894 is a medium-severity vulnerability in Linux kernel, published on 21 Aug 2024. 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-2023-52894 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-2023-52894/ (Markdown: https://insights.sbomify.com/CVE-2023-52894/index.md)","id":"CVE-2023-52894","markdown":"https://insights.sbomify.com/CVE-2023-52894/index.md","name":"CVE-2023-52894","record":{"aliases":["BELL-CVE-2023-52894","DEBIAN-CVE-2023-52894","GHSA-9r79-4jhv-2rfr","UBUNTU-CVE-2023-52894"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel USB gadget","requires_auth":"low_privilege","summary":"A NULL pointer dereference in the Linux kernel's NCM USB gadget driver can cause a system crash, leading to denial of service.","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":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":[{"id":"CWE-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nusb: gadget: f_ncm: fix potential NULL ptr deref in ncm_bitrate()\n\nIn Google internal bug 265639009 we've received an (as yet) unreproducible\ncrash report from an aarch64 GKI 5.10.149-android13 running device.\n\nAFAICT the source code is at:\n  https://android.googlesource.com/kernel/common/+/refs/tags/ASB-2022-12-05_13-5.10\n\nThe call stack is:\n  ncm_close() -\u003e ncm_notify() -\u003e ncm_do_notify()\nwith the crash at:\n  ncm_do_notify+0x98/0x270\nCode: 79000d0b b9000a6c f940012a f9400269 (b9405d4b)\n\nWhich I believe disassembles to (I don't know ARM assembly, but it looks sane enough to me...):\n\n  // halfword (16-bit) store presumably to event-\u003ewLength (at offset 6 of struct usb_cdc_notification)\n  0B 0D 00 79    strh w11, [x8, #6]\n\n  // word (32-bit) store presumably to req-\u003eLength (at offset 8 of struct usb_request)\n  6C 0A 00 B9    str  w12, [x19, #8]\n\n  // x10 (NULL) was read here from offset 0 of valid pointer x9\n  // IMHO we're reading 'cdev-\u003egadget' and getting NULL\n  // gadget is indeed at offset 0 of struct usb_composite_dev\n  2A 01 40 F9    ldr  x10, [x9]\n\n  // loading req-\u003ebuf pointer, which is at offset 0 of struct usb_request\n  69 02 40 F9    ldr  x9, [x19]\n\n  // x10 is null, crash, appears to be attempt to read cdev-\u003egadget-\u003emax_speed\n  4B 5D 40 B9    ldr  w11, [x10, #0x5c]\n\nwhich seems to line up with ncm_do_notify() case NCM_NOTIFY_SPEED code fragment:\n\n  event-\u003ewLength = cpu_to_le16(8);\n  req-\u003elength = NCM_STATUS_BYTECOUNT;\n\n  /* SPEED_CHANGE data is up/down speeds in bits/sec */\n  data = req-\u003ebuf + sizeof *event;\n  data[0] = cpu_to_le32(ncm_bitrate(cdev-\u003egadget));\n\nMy analysis of registers and NULL ptr deref crash offset\n  (Unable to handle kernel NULL pointer dereference at virtual address 000000000000005c)\nheavily suggests that the crash is due to 'cdev-\u003egadget' being NULL when executing:\n  data[0] = cpu_to_le32(ncm_bitrate(cdev-\u003egadget));\nwhich calls:\n  ncm_bitrate(NULL)\nwhich then calls:\n  gadget_is_superspeed(NULL)\nwhich reads\n  ((struct usb_gadget *)NULL)-\u003emax_speed\nand hits a panic.\n\nAFAICT, if I'm counting right, the offset of max_speed is indeed 0x5C.\n(remember there's a GKI KABI reservation of 16 bytes in struct work_struct)\n\nIt's not at all clear to me how this is all supposed to work...\nbut returning 0 seems much better than panic-ing...","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":"usb: gadget: f_ncm: fix potential NULL ptr deref in ncm_bitrate()","id":"CVE-2023-52894","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":7,"next":{"headline":"io_uring/poll: don't reissue in case of poll race on multishot request","id":"CVE-2023-52895"},"packages":[],"prev":{"headline":"gsmi: fix null-deref in gsmi_get_variable","id":"CVE-2023-52893"},"products":["Linux"],"published":"2024-08-21","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":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A NULL pointer dereference in the Linux kernel's NCM USB gadget driver can cause a system crash, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2023-52894/"}