{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2025-21737 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-21737 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Feb 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-2025-21737 and fix it if it is affected.\n\nWhat it is: CVE-2025-21737 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Feb 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-2025-21737 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-2025-21737/ (Markdown: https://insights.sbomify.com/CVE-2025-21737/index.md)","id":"CVE-2025-21737","markdown":"https://insights.sbomify.com/CVE-2025-21737/index.md","name":"CVE-2025-21737","record":{"aliases":["BELL-CVE-2025-21737","DEBIAN-CVE-2025-21737","GHSA-755w-2h7x-xvj6","UBUNTU-CVE-2025-21737"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel CephFS","requires_auth":"low_privilege","summary":"A memory leak in the Linux kernel CephFS module allows attackers to cause a system crash via kernel OOM by accessing files with path-scoped capabilities.","user_interaction":"not_required","vuln_class":"denial_of_service"},"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-401","name":"Missing Release of Memory after Effective Lifetime"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nceph: fix memory leak in ceph_mds_auth_match()\n\nWe now free the temporary target path substring allocation on every\npossible branch, instead of omitting the default branch.  In some\ncases, a memory leak occured, which could rapidly crash the system\n(depending on how many file accesses were attempted).\n\nThis was detected in production because it caused a continuous memory\ngrowth, eventually triggering kernel OOM and completely hard-locking\nthe kernel.\n\nRelevant kmemleak stacktrace:\n\n    unreferenced object 0xffff888131e69900 (size 128):\n      comm \"git\", pid 66104, jiffies 4295435999\n      hex dump (first 32 bytes):\n        76 6f 6c 75 6d 65 73 2f 63 6f 6e 74 61 69 6e 65  volumes/containe\n        72 73 2f 67 69 74 65 61 2f 67 69 74 65 61 2f 67  rs/gitea/gitea/g\n      backtrace (crc 2f3bb450):\n        [\u003cffffffffaa68fb49\u003e] __kmalloc_noprof+0x359/0x510\n        [\u003cffffffffc32bf1df\u003e] ceph_mds_check_access+0x5bf/0x14e0 [ceph]\n        [\u003cffffffffc3235722\u003e] ceph_open+0x312/0xd80 [ceph]\n        [\u003cffffffffaa7dd786\u003e] do_dentry_open+0x456/0x1120\n        [\u003cffffffffaa7e3729\u003e] vfs_open+0x79/0x360\n        [\u003cffffffffaa832875\u003e] path_openat+0x1de5/0x4390\n        [\u003cffffffffaa834fcc\u003e] do_filp_open+0x19c/0x3c0\n        [\u003cffffffffaa7e44a1\u003e] do_sys_openat2+0x141/0x180\n        [\u003cffffffffaa7e4945\u003e] __x64_sys_open+0xe5/0x1a0\n        [\u003cffffffffac2cc2f7\u003e] do_syscall_64+0xb7/0x210\n        [\u003cffffffffac400130\u003e] entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nIt can be triggered by mouting a subdirectory of a CephFS filesystem,\nand then trying to access files on this subdirectory with an auth token\nusing a path-scoped capability:\n\n    $ ceph auth get client.services\n    [client.services]\n            key = REDACTED\n            caps mds = \"allow rw fsname=cephfs path=/volumes/\"\n            caps mon = \"allow r fsname=cephfs\"\n            caps osd = \"allow rw tag cephfs data=cephfs\"\n\n    $ cat /proc/self/mounts\n    services@[REDACTED].cephfs=/volumes/containers /ceph/containers ceph rw,noatime,name=services,secret=\u003chidden\u003e,ms_mode=prefer-crc,mount_timeout=300,acl,mon_addr=[REDACTED]:3300,recover_session=clean 0 0\n\n    $ seq 1 1000000 | xargs -P32 --replace={} touch /ceph/containers/file-{} \u0026\u0026 \\\n    seq 1 1000000 | xargs -P32 --replace={} cat /ceph/containers/file-{}\n\n[ idryomov: combine if statements, rename rc to path_matched and make\n            it a bool, formatting ]","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 memory leak in ceph_mds_auth_match()","id":"CVE-2025-21737","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"denial_of_service","year":"2025"},"n_packages":0,"n_references":3,"next":{"headline":"ata: libata-sff: Ensure that we cannot write outside the allocated buffer","id":"CVE-2025-21738"},"packages":[],"prev":{"headline":"nilfs2: fix possible int overflows in nilfs_fiemap()","id":"CVE-2025-21736"},"products":["Linux"],"published":"2025-02-27","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 memory leak in the Linux kernel CephFS module allows attackers to cause a system crash via kernel OOM by accessing files with path-scoped capabilities.","url":"https://insights.sbomify.com/CVE-2025-21737/"}