{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-72343 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-72343 is a high-severity vulnerability in Linux, published on 15 Aug 2026. 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-2026-72343 and fix it if it is affected.\n\nWhat it is: CVE-2026-72343 is a high-severity vulnerability in Linux, published on 15 Aug 2026. 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-2026-72343 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-2026-72343/ (Markdown: https://insights.sbomify.com/CVE-2026-72343/index.md)","id":"CVE-2026-72343","markdown":"https://insights.sbomify.com/CVE-2026-72343/index.md","name":"CVE-2026-72343","record":{"aliases":["BELL-CVE-2026-72343","DEBIAN-CVE-2026-72343","GHSA-4xw9-57x7-f4g8","UBUNTU-CVE-2026-72343"],"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":"none","summary":"A null pointer dereference in the mlx5e driver causes a kernel crash when hypervisor stats are enabled, leading to denial of service.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":8.4,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5e: Fix HV VHCA stats zero-sized buffer allocation\n\nmlx5e_hv_vhca_stats_create() is called from mlx5e_nic_enable(),\nbefore mlx5e_open(). At that point priv-\u003estats_nch is still zero,\nbecause it is only ever incremented in mlx5e_channel_stats_alloc(),\nwhich is reached only from mlx5e_open_channel().\n\nmlx5e_hv_vhca_stats_buf_size() therefore returns 0, and\nkvzalloc(0, GFP_KERNEL) returns ZERO_SIZE_PTR ((void *)16) rather\nthan NULL. The \"if (!buf)\" guard does not catch this, and\nmlx5e_hv_vhca_stats_create() completes \"successfully\" with\npriv-\u003estats_agent.buf set to ZERO_SIZE_PTR.\n\nOnce channels are opened (priv-\u003estats_nch \u003e 0) and the hypervisor\nenables stats reporting, mlx5e_hv_vhca_stats_work() recomputes\nbuf_len using the new non-zero stats_nch and calls\nmemset(buf, 0, buf_len) on ZERO_SIZE_PTR, faulting at address 0x10.\n\nAllocate the buffer based on priv-\u003emax_nch, which is set in\nmlx5e_priv_init() and is the upper bound on stats_nch:\n\n  - Add a separate helper mlx5e_hv_vhca_stats_buf_max_size() that\n    returns sizeof(per_ring_stats) * max(max_nch, stats_nch), and\n    use it for the kvzalloc() in mlx5e_hv_vhca_stats_create().\n  - Keep mlx5e_hv_vhca_stats_buf_size() (which returns based on\n    stats_nch) for the worker's active payload size, so the wire\n    format (block-\u003erings = stats_nch) and the amount of data filled\n    by mlx5e_hv_vhca_fill_stats() are unchanged.\n\nThe max(max_nch, stats_nch) guard handles the rare case where\nmlx5e_attach_netdev() recomputes max_nch downward across a\ndetach/resume cycle while priv-\u003estats_nch persists (mlx5e_detach_netdev\ndoes not call mlx5e_priv_cleanup, so stats_nch is only reset when\nthe netdev is destroyed). Without the guard, the worker could compute\nbuf_len from stats_nch and overrun the smaller buffer allocated based\non the reduced max_nch.\n\nAllocating a non-zero buffer also makes the kvzalloc() failure path in\nmlx5e_hv_vhca_stats_create() reachable for the first time: it returns\nearly without (re)creating the agent. Clear\npriv-\u003estats_agent.{agent,buf} in mlx5e_hv_vhca_stats_destroy() after\nfreeing them, so that if a later create() bails out on this path, a\nsubsequent teardown does not double-free the stale agent/buffer left\nfrom a previous enable/disable cycle.\n\nThis mirrors the existing mlx5e pattern of preallocating arrays of\nsize max_nch (e.g. priv-\u003echannel_stats) and lazily populating\nentries up to stats_nch on demand.","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":"net/mlx5e: Fix HV VHCA stats zero-sized buffer allocation","id":"CVE-2026-72343","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"null_dereference","year":"2026"},"n_packages":0,"n_references":6,"next":{"headline":"net/mlx5e: TC, skip peer flow cleanup when LAG seq is unavailable","id":"CVE-2026-72344"},"packages":[],"prev":{"headline":"net/mlx5e: Fix HV VHCA stats agent registration race","id":"CVE-2026-72342"},"products":["Linux"],"published":"2026-08-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-16","vendors":["Linux"]},"summary":"A null pointer dereference in the mlx5e driver causes a kernel crash when hypervisor stats are enabled, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2026-72343/"}