{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2025-40362 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-40362 is a high-severity missing authorization vulnerability in Linux, published on 16 Dec 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-2025-40362 and fix it if it is affected.\n\nWhat it is: CVE-2025-40362 is a high-severity missing authorization vulnerability in Linux, published on 16 Dec 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-2025-40362 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-2025-40362/ (Markdown: https://insights.sbomify.com/CVE-2025-40362/index.md)","id":"CVE-2025-40362","markdown":"https://insights.sbomify.com/CVE-2025-40362/index.md","name":"CVE-2025-40362","record":{"aliases":["BELL-CVE-2025-40362","DEBIAN-CVE-2025-40362","GHSA-p5mp-qv23-7r77","ROOT-OS-DEBIAN-13-CVE-2025-40362","ROOT-OS-UBUNTU-2204-CVE-2025-40362","ROOT-OS-UBUNTU-2404-CVE-2025-40362","UBUNTU-CVE-2025-40362"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["privilege_escalation","data_modify"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel Ceph","requires_auth":"low_privilege","summary":"A flaw in the Linux kernel Ceph client allows users to bypass read-only restrictions on one filesystem by leveraging write permissions on another in multi-filesystem clusters.","user_interaction":"not_required","vuln_class":"missing_authorization"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":8.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nceph: fix multifs mds auth caps issue\n\nThe mds auth caps check should also validate the\nfsname along with the associated caps. Not doing\nso would result in applying the mds auth caps of\none fs on to the other fs in a multifs ceph cluster.\nThe bug causes multiple issues w.r.t user\nauthentication, following is one such example.\n\nSteps to Reproduce (on vstart cluster):\n1. Create two file systems in a cluster, say 'fsname1' and 'fsname2'\n2. Authorize read only permission to the user 'client.usr' on fs 'fsname1'\n    $ceph fs authorize fsname1 client.usr / r\n3. Authorize read and write permission to the same user 'client.usr' on fs 'fsname2'\n    $ceph fs authorize fsname2 client.usr / rw\n4. Update the keyring\n    $ceph auth get client.usr \u003e\u003e ./keyring\n\nWith above permssions for the user 'client.usr', following is the\nexpectation.\n  a. The 'client.usr' should be able to only read the contents\n     and not allowed to create or delete files on file system 'fsname1'.\n  b. The 'client.usr' should be able to read/write on file system 'fsname2'.\n\nBut, with this bug, the 'client.usr' is allowed to read/write on file\nsystem 'fsname1'. See below.\n\n5. Mount the file system 'fsname1' with the user 'client.usr'\n     $sudo bin/mount.ceph usr@.fsname1=/ /kmnt_fsname1_usr/\n6. Try creating a file on file system 'fsname1' with user 'client.usr'. This\n   should fail but passes with this bug.\n     $touch /kmnt_fsname1_usr/file1\n7. Mount the file system 'fsname1' with the user 'client.admin' and create a\n   file.\n     $sudo bin/mount.ceph admin@.fsname1=/ /kmnt_fsname1_admin\n     $echo \"data\" \u003e /kmnt_fsname1_admin/admin_file1\n8. Try removing an existing file on file system 'fsname1' with the user\n   'client.usr'. This shoudn't succeed but succeeds with the bug.\n     $rm -f /kmnt_fsname1_usr/admin_file1\n\nFor more information, please take a look at the corresponding mds/fuse patch\nand tests added by looking into the tracker mentioned below.\n\nv2: Fix a possible null dereference in doutc\nv3: Don't store fsname from mdsmap, validate against\n    ceph_mount_options's fsname and use it\nv4: Code refactor, better warning message and\n    fix possible compiler warning\n\n[ Slava.Dubeyko: \"fsname check failed\" -\u003e \"fsname mismatch\" ]","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":"ceph: fix multifs mds auth caps issue","id":"CVE-2025-40362","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"missing_authorization","year":"2025"},"n_packages":0,"n_references":3,"next":{"headline":"net: ipv6: fix field-spanning memcpy warning in AH output","id":"CVE-2025-40363"},"packages":[],"prev":{"headline":"This CVE ID has been rejected or withdrawn by its CVE Numbering Authority.","id":"CVE-2025-40361"},"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":"total"},"state":"PUBLISHED","updated":"2026-10-15","vendors":["Linux"]},"summary":"A flaw in the Linux kernel Ceph client allows users to bypass read-only restrictions on one filesystem by leveraging write permissions on another in multi-filesystem clusters.","url":"https://insights.sbomify.com/CVE-2025-40362/"}