{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2025-21670 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-21670 is a medium-severity vulnerability in Linux kernel, published on 31 Jan 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-2025-21670 and fix it if it is affected.\n\nWhat it is: CVE-2025-21670 is a medium-severity vulnerability in Linux kernel, published on 31 Jan 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-2025-21670 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-2025-21670/ (Markdown: https://insights.sbomify.com/CVE-2025-21670/index.md)","id":"CVE-2025-21670","markdown":"https://insights.sbomify.com/CVE-2025-21670/index.md","name":"CVE-2025-21670","record":{"aliases":["AZL-56396","BELL-CVE-2025-21670","DEBIAN-CVE-2025-21670","GHSA-9w9r-vq29-w437","UBUNTU-CVE-2025-21670"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A local attacker can trigger a kernel crash by calling recvfrom on a vsock socket with an unassigned transport, causing a null pointer dereference.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"cisa-adp","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nvsock/bpf: return early if transport is not assigned\n\nSome of the core functions can only be called if the transport\nhas been assigned.\n\nAs Michal reported, a socket might have the transport at NULL,\nfor example after a failed connect(), causing the following trace:\n\n    BUG: kernel NULL pointer dereference, address: 00000000000000a0\n    #PF: supervisor read access in kernel mode\n    #PF: error_code(0x0000) - not-present page\n    PGD 12faf8067 P4D 12faf8067 PUD 113670067 PMD 0\n    Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI\n    CPU: 15 UID: 0 PID: 1198 Comm: a.out Not tainted 6.13.0-rc2+\n    RIP: 0010:vsock_connectible_has_data+0x1f/0x40\n    Call Trace:\n     vsock_bpf_recvmsg+0xca/0x5e0\n     sock_recvmsg+0xb9/0xc0\n     __sys_recvfrom+0xb3/0x130\n     __x64_sys_recvfrom+0x20/0x30\n     do_syscall_64+0x93/0x180\n     entry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nSo we need to check the `vsk-\u003etransport` in vsock_bpf_recvmsg(),\nespecially for connected sockets (stream/seqpacket) as we already\ndo in __vsock_connectible_recvmsg().","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":"vsock/bpf: return early if transport is not assigned","id":"CVE-2025-21670","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2025"},"n_packages":0,"n_references":3,"next":{"headline":"zram: fix potential UAF of zram table","id":"CVE-2025-21671"},"packages":[],"prev":{"headline":"vsock/virtio: discard packets if the transport changes","id":"CVE-2025-21669"},"products":["Linux"],"published":"2025-01-31","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":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A local attacker can trigger a kernel crash by calling recvfrom on a vsock socket with an unassigned transport, causing a null pointer dereference.","url":"https://insights.sbomify.com/CVE-2025-21670/"}