{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-53221 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-53221 is a critical vulnerability in Linux kernel, published on 25 Jun 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-2026-53221 and fix it if it is affected.\n\nWhat it is: CVE-2026-53221 is a critical vulnerability in Linux kernel, published on 25 Jun 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-2026-53221 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-2026-53221/ (Markdown: https://insights.sbomify.com/CVE-2026-53221/index.md)","id":"CVE-2026-53221","markdown":"https://insights.sbomify.com/CVE-2026-53221/index.md","name":"CVE-2026-53221","record":{"aliases":["AZL-90807","BELL-CVE-2026-53221","DEBIAN-CVE-2026-53221","GHSA-h3c9-j2j5-6mff","ROOT-OS-DEBIAN-11-CVE-2026-53221","ROOT-OS-DEBIAN-12-CVE-2026-53221","ROOT-OS-UBUNTU-2204-CVE-2026-53221","ROOT-OS-UBUNTU-2404-CVE-2026-53221","UBUNTU-CVE-2026-53221"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["other"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel","requires_auth":"none","summary":"Incorrect tunnel matching in Linux kernel IPv6 VTI allows potential traffic misrouting due to missing wildcard checks.","user_interaction":"not_required","vuln_class":"other"},"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":[{"id":"CWE-20","name":"Improper Input Validation"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nip6_vti: fix incorrect tunnel matching in vti6_tnl_lookup()\n\nIn vti6_tnl_lookup(), when an exact match for a tunnel fails,\nthe code falls back to searching for wildcard tunnels:\n\n- Tunnels matching the packet's local address, with any remote address\n  wildcard remote).\n\n- Tunnels matching the packet's remote address, with any local address\n  (wildcard local).\n\nHowever, vti6 stores all these different types of tunnels in the same\nhash table (ip6n-\u003etnls_r_l) prone to hash collisions.\n\nThe bug is that the fallback search loops in vti6_tnl_lookup() were\nmissing checks to ensure that the candidate tunnel actually has\na wildcard address.","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":"ip6_vti: fix incorrect tunnel matching in vti6_tnl_lookup()","id":"CVE-2026-53221","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"other","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"ptp: ocp: fix resource freeing order","id":"CVE-2026-53222"},"packages":[],"prev":{"headline":"netfilter: revalidate bridge ports","id":"CVE-2026-53220"},"products":["Linux"],"published":"2026-06-25","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":"yes","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"Incorrect tunnel matching in Linux kernel IPv6 VTI allows potential traffic misrouting due to missing wildcard checks.","url":"https://insights.sbomify.com/CVE-2026-53221/"}