{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-63817 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-63817 is a high-severity missing authorization vulnerability in Linux, published on 19 Jul 2026. 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-2026-63817 and fix it if it is affected.\n\nWhat it is: CVE-2026-63817 is a high-severity missing authorization vulnerability in Linux, published on 19 Jul 2026. 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-2026-63817 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-2026-63817/ (Markdown: https://insights.sbomify.com/CVE-2026-63817/index.md)","id":"CVE-2026-63817","markdown":"https://insights.sbomify.com/CVE-2026-63817/index.md","name":"CVE-2026-63817","record":{"aliases":["BELL-CVE-2026-63817","DEBIAN-CVE-2026-63817","GHSA-cv79-fx5q-34h3","ROOT-OS-UBUNTU-2204-CVE-2026-63817","UBUNTU-CVE-2026-63817"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["privilege_escalation","data_read"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel filesystem","requires_auth":"low_privilege","summary":"Attackers can bypass inode validation in F2FS when compression cache is disabled, potentially accessing internal kernel structures or escalating privileges.","user_interaction":"not_required","vuln_class":"missing_authorization"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"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\nf2fs: validate compress cache inode only when enabled\n\nF2FS_COMPRESS_INO() uses NM_I(sbi)-\u003emax_nid as the synthetic inode\nnumber for the compressed page cache inode. That inode only exists when\nthe compress_cache mount option is enabled.\n\nWhen compress_cache is disabled, max_nid is outside the valid inode\nrange. A corrupted directory entry that points to ino == max_nid should\ntherefore be rejected by f2fs_check_nid_range(). However, is_meta_ino()\ncurrently treats F2FS_COMPRESS_INO() as a meta inode unconditionally,\nso f2fs_iget() bypasses do_read_inode() and its nid range check, and\ninstantiates a fake internal inode instead.\n\nGate the compressed cache inode case on COMPRESS_CACHE, matching\nf2fs_init_compress_inode(). With compress_cache disabled, ino ==\nmax_nid now follows the normal inode path and is rejected as an\nout-of-range nid.","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":"f2fs: validate compress cache inode only when enabled","id":"CVE-2026-63817","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"missing_authorization","year":"2026"},"n_packages":0,"n_references":7,"next":{"headline":"f2fs: validate orphan inode entry count","id":"CVE-2026-63818"},"packages":[],"prev":{"headline":"f2fs: atomic: fix UAF issue on f2fs_inode_info.atomic_inode","id":"CVE-2026-63816"},"products":["Linux"],"published":"2026-07-19","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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-08-17","vendors":["Linux"]},"summary":"Attackers can bypass inode validation in F2FS when compression cache is disabled, potentially accessing internal kernel structures or escalating privileges.","url":"https://insights.sbomify.com/CVE-2026-63817/"}