{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-98987 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-98987 is a vulnerability in Linux, published on 23 Oct 2026."},"fix_prompt":"Check this codebase for CVE-2026-98987 and fix it if it is affected.\n\nWhat it is: CVE-2026-98987 is a vulnerability in Linux, published on 23 Oct 2026. \nExploitation: There is no known exploitation of CVE-2026-98987 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-2026-98987/ (Markdown: https://insights.sbomify.com/CVE-2026-98987/index.md)","id":"CVE-2026-98987","markdown":"https://insights.sbomify.com/CVE-2026-98987/index.md","name":"CVE-2026-98987","record":{"aliases":["BELL-CVE-2026-98987","DEBIAN-CVE-2026-98987","GHSA-8fp8-xwh3-vf8f","UBUNTU-CVE-2026-98987"],"analysis":null,"analysis_generated_by":null,"assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnamespace: look at the topmost mount for a mount namespace file\n\nattach_recursive_mnt() preallocates a mountpoint for the root of the\ntopmost mount of the source so that a mount that already sits at the\ndestination can be put on top of the source or on top of one of its\npropagated copies.\n\nThe copies are made without CL_COPY_MNT_NS_FILE so their chain of\novermounts is shorter than the source's. It ends below the first bind\nmount of a mount namespace file. So while the loop walks up the chain of\nthe source it remembers the mountpoint of that mount in \"shorter\" and\nthe existing mount is put there for the copies.\n\nBut the loop ends at the topmost mount without ever looking at it. If\nthe topmost mount is the only mount namespace file in the chain\n\"shorter\" stays NULL and mnt_change_mountpoint() attaches the existing\nmount of the copy below the root of the mount namespace file. That's a\ndentry of nsfs. No path walk in the copy's mount namespace ever gets\nthere. The mount is gone until its parent goes and the copy that took\nits place can't be unmounted synchronously because it has a child:\n\n  S      bind mount of a file\n  N      bind mount of a mount namespace file on top of S\n  A      shared mount, B a slave of A, Q mounted on B/file\n\n  move_mount(S, A/file)\n  cat B/file          -\u003e the content of S instead of Q\n  umount B/file       -\u003e EBUSY\n\nLook at every mount of the chain including the topmost one.","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":"namespace: look at the topmost mount for a mount namespace file","id":"CVE-2026-98987","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":null,"year":"2026"},"n_packages":0,"n_references":3,"next":{"headline":"namespace: keep covered mounts covered in OPEN_TREE_NAMESPACE","id":"CVE-2026-98988"},"packages":[],"prev":{"headline":"namespace: remove the fsnotify marks of a mount namespace in process context","id":"CVE-2026-98986"},"products":["Linux"],"published":"2026-10-23","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-23","vendors":["Linux"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2026-98987/"}