{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2025-68241 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-68241 is a high-severity vulnerability in Linux, published on 16 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2025-68241 and fix it if it is affected.\n\nWhat it is: CVE-2025-68241 is a high-severity vulnerability in Linux, published on 16 Dec 2025. 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-2025-68241 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-2025-68241/ (Markdown: https://insights.sbomify.com/CVE-2025-68241/index.md)","id":"CVE-2025-68241","markdown":"https://insights.sbomify.com/CVE-2025-68241/index.md","name":"CVE-2025-68241","record":{"aliases":["BELL-CVE-2025-68241","DEBIAN-CVE-2025-68241","GHSA-vwj6-rppm-qjrp","ROOT-OS-DEBIAN-12-CVE-2025-68241","ROOT-OS-DEBIAN-13-CVE-2025-68241","ROOT-OS-UBUNTU-2204-CVE-2025-68241","ROOT-OS-UBUNTU-2404-CVE-2025-68241","UBUNTU-CVE-2025-68241"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel","requires_auth":"none","summary":"A race condition in the Linux kernel IPv4 routing code can cause a device reference count leak, leading to denial of service when unregistering network devices.","user_interaction":"not_required","vuln_class":"race_condition"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":7.5,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv4: route: Prevent rt_bind_exception() from rebinding stale fnhe\n\nThe sit driver's packet transmission path calls: sit_tunnel_xmit() -\u003e\nupdate_or_create_fnhe(), which lead to fnhe_remove_oldest() being called\nto delete entries exceeding FNHE_RECLAIM_DEPTH+random.\n\nThe race window is between fnhe_remove_oldest() selecting fnheX for\ndeletion and the subsequent kfree_rcu(). During this time, the\nconcurrent path's __mkroute_output() -\u003e find_exception() can fetch the\nsoon-to-be-deleted fnheX, and rt_bind_exception() then binds it with a\nnew dst using a dst_hold(). When the original fnheX is freed via RCU,\nthe dst reference remains permanently leaked.\n\nCPU 0                             CPU 1\n__mkroute_output()\n  find_exception() [fnheX]\n                                  update_or_create_fnhe()\n                                    fnhe_remove_oldest() [fnheX]\n  rt_bind_exception() [bind dst]\n                                  RCU callback [fnheX freed, dst leak]\n\nThis issue manifests as a device reference count leak and a warning in\ndmesg when unregistering the net device:\n\n  unregister_netdevice: waiting for sitX to become free. Usage count = N\n\nIdo Schimmel provided the simple test validation method [1].\n\nThe fix clears 'oldest-\u003efnhe_daddr' before calling fnhe_flush_routes().\nSince rt_bind_exception() checks this field, setting it to zero prevents\nthe stale fnhe from being reused and bound to a new dst just before it\nis freed.\n\n[1]\nip netns add ns1\nip -n ns1 link set dev lo up\nip -n ns1 address add 192.0.2.1/32 dev lo\nip -n ns1 link add name dummy1 up type dummy\nip -n ns1 route add 192.0.2.2/32 dev dummy1\nip -n ns1 link add name gretap1 up arp off type gretap \\\n    local 192.0.2.1 remote 192.0.2.2\nip -n ns1 route add 198.51.0.0/16 dev gretap1\ntaskset -c 0 ip netns exec ns1 mausezahn gretap1 \\\n    -A 198.51.100.1 -B 198.51.0.0/16 -t udp -p 1000 -c 0 -q \u0026\ntaskset -c 2 ip netns exec ns1 mausezahn gretap1 \\\n    -A 198.51.100.1 -B 198.51.0.0/16 -t udp -p 1000 -c 0 -q \u0026\nsleep 10\nip netns pids ns1 | xargs kill\nip netns del ns1","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":"ipv4: route: Prevent rt_bind_exception() from rebinding stale fnhe","id":"CVE-2025-68241","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"race_condition","year":"2025"},"n_packages":0,"n_references":8,"next":{"headline":"NFS: Fix LTP test failures when timestamps are delegated","id":"CVE-2025-68242"},"packages":[],"prev":{"headline":"nilfs2: avoid having an active sc_timer before freeing sci","id":"CVE-2025-68240"},"products":["Linux"],"published":"2025-12-16","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":"partial"},"state":"PUBLISHED","updated":"2026-08-05","vendors":["Linux"]},"summary":"A race condition in the Linux kernel IPv4 routing code can cause a device reference count leak, leading to denial of service when unregistering network devices.","url":"https://insights.sbomify.com/CVE-2025-68241/"}