{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-43465 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-43465 is a critical memory corruption vulnerability in Linux kernel, published on 8 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-43465 and fix it if it is affected.\n\nWhat it is: CVE-2026-43465 is a critical memory corruption vulnerability in Linux kernel, published on 8 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-43465 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-2026-43465/ (Markdown: https://insights.sbomify.com/CVE-2026-43465/index.md)","id":"CVE-2026-43465","markdown":"https://insights.sbomify.com/CVE-2026-43465/index.md","name":"CVE-2026-43465","record":{"aliases":["AZL-87060","BELL-CVE-2026-43465","DEBIAN-CVE-2026-43465","GHSA-wm82-xv2w-22mm","ROOT-OS-DEBIAN-13-CVE-2026-43465","ROOT-OS-UBUNTU-2404-CVE-2026-43465","UBUNTU-CVE-2026-43465"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel driver","requires_auth":"none","summary":"A reference counting error in the mlx5 network driver can cause negative page reference counts, leading to kernel warnings and potential system instability.","user_interaction":"not_required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":9.8,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/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: RX, Fix XDP multi-buf frag counting for striding RQ\n\nXDP multi-buf programs can modify the layout of the XDP buffer when the\nprogram calls bpf_xdp_pull_data() or bpf_xdp_adjust_tail(). The\nreferenced commit in the fixes tag corrected the assumption in the mlx5\ndriver that the XDP buffer layout doesn't change during a program\nexecution. However, this fix introduced another issue: the dropped\nfragments still need to be counted on the driver side to avoid page\nfragment reference counting issues.\n\nThe issue was discovered by the drivers/net/xdp.py selftest,\nmore specifically the test_xdp_native_tx_mb:\n- The mlx5 driver allocates a page_pool page and initializes it with\n  a frag counter of 64 (pp_ref_count=64) and the internal frag counter\n  to 0.\n- The test sends one packet with no payload.\n- On RX (mlx5e_skb_from_cqe_mpwrq_nonlinear()), mlx5 configures the XDP\n  buffer with the packet data starting in the first fragment which is the\n  page mentioned above.\n- The XDP program runs and calls bpf_xdp_pull_data() which moves the\n  header into the linear part of the XDP buffer. As the packet doesn't\n  contain more data, the program drops the tail fragment since it no\n  longer contains any payload (pp_ref_count=63).\n- mlx5 device skips counting this fragment. Internal frag counter\n  remains 0.\n- mlx5 releases all 64 fragments of the page but page pp_ref_count is\n  63 =\u003e negative reference counting error.\n\nResulting splat during the test:\n\n  WARNING: CPU: 0 PID: 188225 at ./include/net/page_pool/helpers.h:297 mlx5e_page_release_fragmented.isra.0+0xbd/0xe0 [mlx5_core]\n  Modules linked in: [...]\n  CPU: 0 UID: 0 PID: 188225 Comm: ip Not tainted 6.18.0-rc7_for_upstream_min_debug_2025_12_08_11_44 #1 NONE\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\n  RIP: 0010:mlx5e_page_release_fragmented.isra.0+0xbd/0xe0 [mlx5_core]\n  [...]\n  Call Trace:\n   \u003cTASK\u003e\n   mlx5e_free_rx_mpwqe+0x20a/0x250 [mlx5_core]\n   mlx5e_dealloc_rx_mpwqe+0x37/0xb0 [mlx5_core]\n   mlx5e_free_rx_descs+0x11a/0x170 [mlx5_core]\n   mlx5e_close_rq+0x78/0xa0 [mlx5_core]\n   mlx5e_close_queues+0x46/0x2a0 [mlx5_core]\n   mlx5e_close_channel+0x24/0x90 [mlx5_core]\n   mlx5e_close_channels+0x5d/0xf0 [mlx5_core]\n   mlx5e_safe_switch_params+0x2ec/0x380 [mlx5_core]\n   mlx5e_change_mtu+0x11d/0x490 [mlx5_core]\n   mlx5e_change_nic_mtu+0x19/0x30 [mlx5_core]\n   netif_set_mtu_ext+0xfc/0x240\n   do_setlink.isra.0+0x226/0x1100\n   rtnl_newlink+0x7a9/0xba0\n   rtnetlink_rcv_msg+0x220/0x3c0\n   netlink_rcv_skb+0x4b/0xf0\n   netlink_unicast+0x255/0x380\n   netlink_sendmsg+0x1f3/0x420\n   __sock_sendmsg+0x38/0x60\n   ____sys_sendmsg+0x1e8/0x240\n   ___sys_sendmsg+0x7c/0xb0\n   [...]\n   __sys_sendmsg+0x5f/0xb0\n   do_syscall_64+0x55/0xc70\n\nThe problem applies for XDP_PASS as well which is handled in a different\ncode path in the driver.\n\nThis patch fixes the issue by doing page frag counting on all the\noriginal XDP buffer fragments for all relevant XDP actions (XDP_TX ,\nXDP_REDIRECT and XDP_PASS). This is basically reverting to the original\ncounting before the commit in the fixes tag.\n\nAs frag_page is still pointing to the original tail, the nr_frags\nparameter to xdp_update_skb_frags_info() needs to be calculated\nin a different way to reflect the new nr_frags.","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: RX, Fix XDP multi-buf frag counting for striding RQ","id":"CVE-2026-43465","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"memory_corruption","year":"2026"},"n_packages":0,"n_references":5,"next":{"headline":"net/mlx5e: Fix DMA FIFO desync on error CQE SQ recovery","id":"CVE-2026-43466"},"packages":[],"prev":{"headline":"net/mlx5e: RX, Fix XDP multi-buf frag counting for legacy RQ","id":"CVE-2026-43464"},"products":["Linux"],"published":"2026-05-08","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":"2026-10-21","vendors":["Linux"]},"summary":"A reference counting error in the mlx5 network driver can cause negative page reference counts, leading to kernel warnings and potential system instability.","url":"https://insights.sbomify.com/CVE-2026-43465/"}