{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2025-38470 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-38470 is a high-severity vulnerability in Debian Debian Linux, published on 28 Jul 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-2025-38470 and fix it if it is affected.\n\nWhat it is: CVE-2025-38470 is a high-severity vulnerability in Debian Debian Linux, published on 28 Jul 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-2025-38470 in the wild and no public exploit code.\n\nAffected product: Debian Debian 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-2025-38470/ (Markdown: https://insights.sbomify.com/CVE-2025-38470/index.md)","id":"CVE-2025-38470","markdown":"https://insights.sbomify.com/CVE-2025-38470/index.md","name":"CVE-2025-38470","record":{"aliases":["AZL-65928","AZL-72968","BELL-CVE-2025-38470","DEBIAN-CVE-2025-38470","GHSA-wcqx-2f73-xqmx","ROOT-OS-DEBIAN-11-CVE-2025-38470","ROOT-OS-UBUNTU-2204-CVE-2025-38470","ROOT-OS-UBUNTU-2404-CVE-2025-38470","UBUNTU-CVE-2025-38470"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel networking","requires_auth":"low_privilege","summary":"A local attacker can trigger a kernel crash via null pointer dereference by toggling VLAN filtering features on network interfaces.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"debian_linux","vendor":"debian"},{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/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: vlan: fix VLAN 0 refcount imbalance of toggling filtering during runtime\n\nAssuming the \"rx-vlan-filter\" feature is enabled on a net device, the\n8021q module will automatically add or remove VLAN 0 when the net device\nis put administratively up or down, respectively. There are a couple of\nproblems with the above scheme.\n\nThe first problem is a memory leak that can happen if the \"rx-vlan-filter\"\nfeature is disabled while the device is running:\n\n # ip link add bond1 up type bond mode 0\n # ethtool -K bond1 rx-vlan-filter off\n # ip link del dev bond1\n\nWhen the device is put administratively down the \"rx-vlan-filter\"\nfeature is disabled, so the 8021q module will not remove VLAN 0 and the\nmemory will be leaked [1].\n\nAnother problem that can happen is that the kernel can automatically\ndelete VLAN 0 when the device is put administratively down despite not\nadding it when the device was put administratively up since during that\ntime the \"rx-vlan-filter\" feature was disabled. null-ptr-unref or\nbug_on[2] will be triggered by unregister_vlan_dev() for refcount\nimbalance if toggling filtering during runtime:\n\n$ ip link add bond0 type bond mode 0\n$ ip link add link bond0 name vlan0 type vlan id 0 protocol 802.1q\n$ ethtool -K bond0 rx-vlan-filter off\n$ ifconfig bond0 up\n$ ethtool -K bond0 rx-vlan-filter on\n$ ifconfig bond0 down\n$ ip link del vlan0\n\nRoot cause is as below:\nstep1: add vlan0 for real_dev, such as bond, team.\nregister_vlan_dev\n    vlan_vid_add(real_dev,htons(ETH_P_8021Q),0) //refcnt=1\nstep2: disable vlan filter feature and enable real_dev\nstep3: change filter from 0 to 1\nvlan_device_event\n    vlan_filter_push_vids\n        ndo_vlan_rx_add_vid //No refcnt added to real_dev vlan0\nstep4: real_dev down\nvlan_device_event\n    vlan_vid_del(dev, htons(ETH_P_8021Q), 0); //refcnt=0\n        vlan_info_rcu_free //free vlan0\nstep5: delete vlan0\nunregister_vlan_dev\n    BUG_ON(!vlan_info); //vlan_info is null\n\nFix both problems by noting in the VLAN info whether VLAN 0 was\nautomatically added upon NETDEV_UP and based on that decide whether it\nshould be deleted upon NETDEV_DOWN, regardless of the state of the\n\"rx-vlan-filter\" feature.\n\n[1]\nunreferenced object 0xffff8880068e3100 (size 256):\n  comm \"ip\", pid 384, jiffies 4296130254\n  hex dump (first 32 bytes):\n    00 20 30 0d 80 88 ff ff 00 00 00 00 00 00 00 00  . 0.............\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n  backtrace (crc 81ce31fa):\n    __kmalloc_cache_noprof+0x2b5/0x340\n    vlan_vid_add+0x434/0x940\n    vlan_device_event.cold+0x75/0xa8\n    notifier_call_chain+0xca/0x150\n    __dev_notify_flags+0xe3/0x250\n    rtnl_configure_link+0x193/0x260\n    rtnl_newlink_create+0x383/0x8e0\n    __rtnl_newlink+0x22c/0xa40\n    rtnl_newlink+0x627/0xb00\n    rtnetlink_rcv_msg+0x6fb/0xb70\n    netlink_rcv_skb+0x11f/0x350\n    netlink_unicast+0x426/0x710\n    netlink_sendmsg+0x75a/0xc20\n    __sock_sendmsg+0xc1/0x150\n    ____sys_sendmsg+0x5aa/0x7b0\n    ___sys_sendmsg+0xfc/0x180\n\n[2]\nkernel BUG at net/8021q/vlan.c:99!\nOops: invalid opcode: 0000 [#1] SMP KASAN PTI\nCPU: 0 UID: 0 PID: 382 Comm: ip Not tainted 6.16.0-rc3 #61 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996),\nBIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\nRIP: 0010:unregister_vlan_dev (net/8021q/vlan.c:99 (discriminator 1))\nRSP: 0018:ffff88810badf310 EFLAGS: 00010246\nRAX: 0000000000000000 RBX: ffff88810da84000 RCX: ffffffffb47ceb9a\nRDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88810e8b43c8\nRBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff6cefe80\nR10: ffffffffb677f407 R11: ffff88810badf3c0 R12: ffff88810e8b4000\nR13: 0000000000000000 R14: ffff88810642a5c0 R15: 000000000000017e\nFS:  00007f1ff68c20c0(0000) GS:ffff888163a24000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007f1ff5dad240 CR3: 0000000107e56000 CR4: 00000000000006f0\nCall Trace:\n \u003cTASK\n---truncated---","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: vlan: fix VLAN 0 refcount imbalance of toggling filtering during runtime","id":"CVE-2025-38470","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"debian:debian_linux","products":["debian:debian_linux","linux:linux_kernel"],"type":"null_dereference","year":"2025"},"n_packages":0,"n_references":8,"next":{"headline":"tls: always refresh the queue when reading sock","id":"CVE-2025-38471"},"packages":[],"prev":{"headline":"KVM: x86/xen: Fix cleanup logic in emulation of Xen schedop poll hypercalls","id":"CVE-2025-38469"},"products":["Linux"],"published":"2025-07-28","related":[{"cvss_score":10,"headline":"ProFTPD Improper Access Control","id":"CVE-2015-3306","kev_date_added":"2026-10-08","published":"2015-05-18"},{"cvss_score":9.9,"headline":"RoundCube Webmail Deserialization of Untrusted Data","id":"CVE-2025-49113","kev_date_added":"2026-02-20","published":"2025-06-02"},{"cvss_score":9.8,"headline":"GNU InetUtils Argument Injection","id":"CVE-2026-24061","kev_date_added":"2026-01-26","published":"2026-01-21"},{"cvss_score":9.8,"headline":"Linux Kernel Improper Check for Unusual or Exceptional Conditions","id":"CVE-2025-39682","kev_date_added":"2026-09-18","published":"2025-09-05"},{"cvss_score":9.8,"headline":"Mozilla Firefox Use-After-Free","id":"CVE-2024-9680","kev_date_added":"2024-10-15","published":"2024-10-09"},{"cvss_score":9.8,"headline":"RARLAB UnRAR Directory Traversal","id":"CVE-2022-30333","kev_date_added":"2022-08-09","published":"2022-05-09"},{"cvss_score":9.8,"headline":"Roundcube Webmail SQL Injection","id":"CVE-2021-44026","kev_date_added":"2023-06-22","published":"2021-11-19"}],"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":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-15","vendors":["Linux"]},"summary":"A local attacker can trigger a kernel crash via null pointer dereference by toggling VLAN filtering features on network interfaces.","url":"https://insights.sbomify.com/CVE-2025-38470/"}