{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2025-37921 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-37921 is a high-severity vulnerability in Debian Debian Linux, published on 20 May 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-2025-37921 and fix it if it is affected.\n\nWhat it is: CVE-2025-37921 is a high-severity vulnerability in Debian Debian Linux, published on 20 May 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-2025-37921 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-2025-37921/ (Markdown: https://insights.sbomify.com/CVE-2025-37921/index.md)","id":"CVE-2025-37921","markdown":"https://insights.sbomify.com/CVE-2025-37921/index.md","name":"CVE-2025-37921","record":{"aliases":["BELL-CVE-2025-37921","DEBIAN-CVE-2025-37921","GHSA-x58j-hw5g-jqcq","ROOT-OS-DEBIAN-12-CVE-2025-37921","ROOT-OS-UBUNTU-2404-CVE-2025-37921","UBUNTU-CVE-2025-37921"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel VXLAN","requires_auth":"low_privilege","summary":"A race condition in the Linux kernel VXLAN driver allows local attackers to trigger a kernel warning and potential denial of service by deleting VNI filters without proper locking.","user_interaction":"not_required","vuln_class":"race_condition"},"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\nvxlan: vnifilter: Fix unlocked deletion of default FDB entry\n\nWhen a VNI is deleted from a VXLAN device in 'vnifilter' mode, the FDB\nentry associated with the default remote (assuming one was configured)\nis deleted without holding the hash lock. This is wrong and will result\nin a warning [1] being generated by the lockdep annotation that was\nadded by commit ebe642067455 (\"vxlan: Create wrappers for FDB lookup\").\n\nReproducer:\n\n # ip link add vx0 up type vxlan dstport 4789 external vnifilter local 192.0.2.1\n # bridge vni add vni 10010 remote 198.51.100.1 dev vx0\n # bridge vni del vni 10010 dev vx0\n\nFix by acquiring the hash lock before the deletion and releasing it\nafterwards. Blame the original commit that introduced the issue rather\nthan the one that exposed it.\n\n[1]\nWARNING: CPU: 3 PID: 392 at drivers/net/vxlan/vxlan_core.c:417 vxlan_find_mac+0x17f/0x1a0\n[...]\nRIP: 0010:vxlan_find_mac+0x17f/0x1a0\n[...]\nCall Trace:\n \u003cTASK\u003e\n __vxlan_fdb_delete+0xbe/0x560\n vxlan_vni_delete_group+0x2ba/0x940\n vxlan_vni_del.isra.0+0x15f/0x580\n vxlan_process_vni_filter+0x38b/0x7b0\n vxlan_vnifilter_process+0x3bb/0x510\n rtnetlink_rcv_msg+0x2f7/0xb70\n netlink_rcv_skb+0x131/0x360\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 __sys_sendmsg+0x121/0x1b0\n do_syscall_64+0xbb/0x1d0\n entry_SYSCALL_64_after_hwframe+0x4b/0x53","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":"vxlan: vnifilter: Fix unlocked deletion of default FDB entry","id":"CVE-2025-37921","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"debian:debian_linux","products":["debian:debian_linux","linux:linux_kernel"],"type":"race_condition","year":"2025"},"n_packages":0,"n_references":5,"next":{"headline":"book3s64/radix : Align section vmemmap start address to PAGE_SIZE","id":"CVE-2025-37922"},"packages":[],"prev":{"headline":"xsk: Fix race condition in AF_XDP generic RX path","id":"CVE-2025-37920"},"products":["Linux"],"published":"2025-05-20","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 race condition in the Linux kernel VXLAN driver allows local attackers to trigger a kernel warning and potential denial of service by deleting VNI filters without proper locking.","url":"https://insights.sbomify.com/CVE-2025-37921/"}