{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-64298 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-64298 is a high-severity missing authorization vulnerability in Linux kernel, published on 25 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-2026-64298 and fix it if it is affected.\n\nWhat it is: CVE-2026-64298 is a high-severity missing authorization vulnerability in Linux kernel, published on 25 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-2026-64298 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-2026-64298/ (Markdown: https://insights.sbomify.com/CVE-2026-64298/index.md)","id":"CVE-2026-64298","markdown":"https://insights.sbomify.com/CVE-2026-64298/index.md","name":"CVE-2026-64298","record":{"aliases":["AZL-93668","BELL-CVE-2026-64298","DEBIAN-CVE-2026-64298","GHSA-mj8v-3x8m-9rx7","ROOT-OS-DEBIAN-12-CVE-2026-64298","ROOT-OS-UBUNTU-2204-CVE-2026-64298","UBUNTU-CVE-2026-64298"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["data_modify"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel NFS","requires_auth":"low_privilege","summary":"An attacker with read-only access can truncate files via NFSv4 due to missing write permission checks during O_TRUNC operations.","user_interaction":"not_required","vuln_class":"missing_authorization"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":7.1,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-862","name":"Missing Authorization"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nNFSv4: include MAY_WRITE in open permission mask for O_TRUNC\n\nPOSIX requires write permission to truncate a file, so an open() that\nspecifies O_TRUNC must be authorized for write access regardless of the\nO_ACCMODE access mode.\n\nnfs_open_permission_mask() builds the access mask passed to\nnfs_may_open(), which is the local authorization gate for OPENs the\nclient serves itself from a cached write delegation via the\ncan_open_delegated() path in nfs4_try_open_cached().  The mask is\nderived from O_ACCMODE alone, so an open(O_RDONLY | O_TRUNC) against a\nfile the caller cannot write requests only MAY_READ and passes the\nlocal check.  The OPEN is then satisfied locally and the truncation is\nissued to the server as a SETATTR(size=0) over the delegation stateid,\nwhich the server accepts under standard write-delegation semantics.\nPOSIX requires that this open fail with EACCES.\n\nInclude MAY_WRITE in the mask whenever O_TRUNC is set so the local\ncheck matches the access the server would have enforced.","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":"NFSv4: include MAY_WRITE in open permission mask for O_TRUNC","id":"CVE-2026-64298","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"missing_authorization","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"tracing: Prevent out-of-bounds read in glob matching","id":"CVE-2026-64299"},"packages":[],"prev":{"headline":"module: decompress: check return value of module_extend_max_pages()","id":"CVE-2026-64297"},"products":["Linux"],"published":"2026-07-25","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":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"An attacker with read-only access can truncate files via NFSv4 due to missing write permission checks during O_TRUNC operations.","url":"https://insights.sbomify.com/CVE-2026-64298/"}