{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-90042 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-90042 is a critical vulnerability in Linux, published on 16 Sep 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-2026-90042 and fix it if it is affected.\n\nWhat it is: CVE-2026-90042 is a critical vulnerability in Linux, published on 16 Sep 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-2026-90042 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-2026-90042/ (Markdown: https://insights.sbomify.com/CVE-2026-90042/index.md)","id":"CVE-2026-90042","markdown":"https://insights.sbomify.com/CVE-2026-90042/index.md","name":"CVE-2026-90042","record":{"aliases":["AZL-101199","BELL-CVE-2026-90042","DEBIAN-CVE-2026-90042","GHSA-39q8-gjm7-pm22","UBUNTU-CVE-2026-90042"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel Ceph","requires_auth":"none","summary":"A kernel bug in Ceph filesystem handling causes crashes when processing filenames in vmalloc buffers, leading to denial of service.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"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":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nceph: properly decrypt filenames in vmalloc() buffers\n\nThe fscrypt subsystem uses the scatterlist crypto API, inheriting its\nrequirement that any buffers are in the linear mapping region. However,\nthe messenger client uses kvmalloc() to create buffers for messages,\nwhich will occasionally place those buffers in the vmalloc() region when\nphysical memory fragmentation doesn't permit a large enough kmalloc().\nThe various callers of ceph_fname_to_usr() directly pass (slices of) raw\nmessages from the MDS without considering that the messages may be in\nvmalloc() buffers, resulting in oopses especially on non-x86 platforms\n(see 'Closes:' for more details and a reproducer).\n\nMake ceph_fname_to_usr() explicitly tolerant of vmalloc()-allocated\nfname-\u003ectext, fname-\u003ename, and/or oname-\u003ename buffers, using `tname`\n(which, when non-null, must be a linear address; when null, is briefly\nallocated as necessary) as a bounce buffer to avoid passing any\ninappropriate addresses to fscrypt_fname_disk_to_usr().\n\nAdditionally change parse_reply_info_readdir() -- the only function to\nsupply its own `tname` -- to follow the new \"tname must never come from\nvmalloc()\" rule by passing NULL when the message is not in the linear\nregion. Though this causes a per-dentry kmalloc()+kfree(), this overhead\nexists only when processing the minority of messages that spill into\nvmalloc(). My (crude) testing puts this at only about 1 in 8,000 readdir\nmessages. Still, if the overhead proves unreasonable in the future, it\nis easy enough to mitigate: a future change could allocate a bounce\nbuffer in parse_reply_info_readdir() and use that as `tname` instead.","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: properly decrypt filenames in vmalloc() buffers","id":"CVE-2026-90042","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"null_dereference","year":"2026"},"n_packages":0,"n_references":5,"next":{"headline":"zram: fix slot lock bit position on big-endian 64-bit","id":"CVE-2026-90043"},"packages":[],"prev":{"headline":"HID: sony: clean up device list on probe failure","id":"CVE-2026-90041"},"products":["Linux"],"published":"2026-09-16","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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-21","vendors":["Linux"]},"summary":"A kernel bug in Ceph filesystem handling causes crashes when processing filenames in vmalloc buffers, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2026-90042/"}