{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-46964 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-46964 is a medium-severity vulnerability in Linux kernel, published on 27 Feb 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-2021-46964 and fix it if it is affected.\n\nWhat it is: CVE-2021-46964 is a medium-severity vulnerability in Linux kernel, published on 27 Feb 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-2021-46964 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-2021-46964/ (Markdown: https://insights.sbomify.com/CVE-2021-46964/index.md)","id":"CVE-2021-46964","markdown":"https://insights.sbomify.com/CVE-2021-46964/index.md","name":"CVE-2021-46964","record":{"aliases":["GHSA-pvcm-vr92-9wx7","UBUNTU-CVE-2021-46964"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel driver","requires_auth":"low_privilege","summary":"A null pointer dereference in the qla2xxx SCSI driver causes a kernel crash when queue pair maps are not allocated, 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\nscsi: qla2xxx: Reserve extra IRQ vectors\n\nCommit a6dcfe08487e (\"scsi: qla2xxx: Limit interrupt vectors to number of\nCPUs\") lowers the number of allocated MSI-X vectors to the number of CPUs.\n\nThat breaks vector allocation assumptions in qla83xx_iospace_config(),\nqla24xx_enable_msix() and qla2x00_iospace_config(). Either of the functions\ncomputes maximum number of qpairs as:\n\n  ha-\u003emax_qpairs = ha-\u003emsix_count - 1 (MB interrupt) - 1 (default\n                   response queue) - 1 (ATIO, in dual or pure target mode)\n\nmax_qpairs is set to zero in case of two CPUs and initiator mode. The\nnumber is then used to allocate ha-\u003equeue_pair_map inside\nqla2x00_alloc_queues(). No allocation happens and ha-\u003equeue_pair_map is\nleft NULL but the driver thinks there are queue pairs available.\n\nqla2xxx_queuecommand() tries to find a qpair in the map and crashes:\n\n  if (ha-\u003emqenable) {\n          uint32_t tag;\n          uint16_t hwq;\n          struct qla_qpair *qpair = NULL;\n\n          tag = blk_mq_unique_tag(cmd-\u003erequest);\n          hwq = blk_mq_unique_tag_to_hwq(tag);\n          qpair = ha-\u003equeue_pair_map[hwq]; # \u003c- HERE\n\n          if (qpair)\n                  return qla2xxx_mqueuecommand(host, cmd, qpair);\n  }\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000000\n  #PF: supervisor read access in kernel mode\n  #PF: error_code(0x0000) - not-present page\n  PGD 0 P4D 0\n  Oops: 0000 [#1] SMP PTI\n  CPU: 0 PID: 72 Comm: kworker/u4:3 Tainted: G        W         5.10.0-rc1+ #25\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014\n  Workqueue: scsi_wq_7 fc_scsi_scan_rport [scsi_transport_fc]\n  RIP: 0010:qla2xxx_queuecommand+0x16b/0x3f0 [qla2xxx]\n  Call Trace:\n   scsi_queue_rq+0x58c/0xa60\n   blk_mq_dispatch_rq_list+0x2b7/0x6f0\n   ? __sbitmap_get_word+0x2a/0x80\n   __blk_mq_sched_dispatch_requests+0xb8/0x170\n   blk_mq_sched_dispatch_requests+0x2b/0x50\n   __blk_mq_run_hw_queue+0x49/0xb0\n   __blk_mq_delay_run_hw_queue+0xfb/0x150\n   blk_mq_sched_insert_request+0xbe/0x110\n   blk_execute_rq+0x45/0x70\n   __scsi_execute+0x10e/0x250\n   scsi_probe_and_add_lun+0x228/0xda0\n   __scsi_scan_target+0xf4/0x620\n   ? __pm_runtime_resume+0x4f/0x70\n   scsi_scan_target+0x100/0x110\n   fc_scsi_scan_rport+0xa1/0xb0 [scsi_transport_fc]\n   process_one_work+0x1ea/0x3b0\n   worker_thread+0x28/0x3b0\n   ? process_one_work+0x3b0/0x3b0\n   kthread+0x112/0x130\n   ? kthread_park+0x80/0x80\n   ret_from_fork+0x22/0x30\n\nThe driver should allocate enough vectors to provide every CPU it's own HW\nqueue and still handle reserved (MB, RSP, ATIO) interrupts.\n\nThe change fixes the crash on dual core VM and prevents unbalanced QP\nallocation where nr_hw_queues is two less than the number of CPUs.","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":"scsi: qla2xxx: Reserve extra IRQ vectors","id":"CVE-2021-46964","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2021"},"n_packages":0,"n_references":3,"next":{"headline":"mtd: physmap: physmap-bt1-rom: Fix unintentional stack access","id":"CVE-2021-46965"},"packages":[],"prev":{"headline":"scsi: qla2xxx: Fix crash in qla2xxx_mqueuecommand()","id":"CVE-2021-46963"},"products":["Linux"],"published":"2024-02-27","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 qla2xxx SCSI driver causes a kernel crash when queue pair maps are not allocated, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2021-46964/"}