{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-98988 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-98988 is a high-severity vulnerability in Linux, published on 23 Oct 2026."},"fix_prompt":"Check this codebase for CVE-2026-98988 and fix it if it is affected.\n\nWhat it is: CVE-2026-98988 is a high-severity vulnerability in Linux, published on 23 Oct 2026. \nExploitation: There is no known exploitation of CVE-2026-98988 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-2026-98988/ (Markdown: https://insights.sbomify.com/CVE-2026-98988/index.md)","id":"CVE-2026-98988","markdown":"https://insights.sbomify.com/CVE-2026-98988/index.md","name":"CVE-2026-98988","record":{"aliases":["DEBIAN-CVE-2026-98988","GHSA-6v5x-qw46-2jph","UBUNTU-CVE-2026-98988"],"analysis":null,"analysis_generated_by":null,"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\nnamespace: keep covered mounts covered in OPEN_TREE_NAMESPACE\n\nopen_tree(OPEN_TREE_NAMESPACE) creates a new mount namespace from a\ncopy of the tree at the given path. The caller needs to be privileged\nover its current user namespace because the new mount namespace will be\nowned by it. It doesn't need to be privileged over the mount namespace\nthe tree is copied from. An unprivileged user just needs to create a\nuser namespace first.\n\nThe copy follows the rules of a detached bind mount. Without\nAT_RECURSIVE only the mount itself is cloned and its children are left\nout. With AT_RECURSIVE unbindable mounts are skipped. Both is fine when\nthe caller has privileges over the source mount namespace because it\ncould unmount those mounts anyway. Not so for an unprivileged user in\nthat mount namespace. For them a mount namespace copy is what unshare()\ndoes. copy_mnt_ns() copies everything including unbindable mounts and\nlock_mnt_tree() makes sure nothing can be unmounted in the copy. Nothing\nthat was covered gets revealed.\n\ncreate_new_namespace() only does the locking and so the covered content\nis right there in the new mount namespace:\n\n  # mount -t tmpfs none /tmp/otn; mkdir /tmp/otn/covered\n  # echo hidden \u003e /tmp/otn/covered/under.txt\n  # mount -t tmpfs none /tmp/otn/covered\n\n  uid 1000, after unshare(CLONE_NEWUSER):\n  fd = open_tree(AT_FDCWD, \"/tmp/otn\", OPEN_TREE_NAMESPACE);\n  setns(fd, CLONE_NEWNS);\n  open(\"/covered/under.txt\", O_RDONLY)  -\u003e \"hidden\"\n\nCovering paths with mounts is how container runtimes mask parts of\n/proc and /sys and how admins hide things.\n\nWhen the caller's user namespace doesn't own the source mount namespace\ncopy the way unshare() does and refuse a non-recursive copy of a mount\nthat has anything mounted below the requested directory and copy\nunbindable mounts in a recursive copy. A caller that is privileged over\nthe source mount namespace sees no change.","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: keep covered mounts covered in OPEN_TREE_NAMESPACE","id":"CVE-2026-98988","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":null,"year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"namespace: check a recursive bind mount for mount namespace loops","id":"CVE-2026-98989"},"packages":[],"prev":{"headline":"namespace: look at the topmost mount for a mount namespace file","id":"CVE-2026-98987"},"products":["Linux"],"published":"2026-10-23","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":"2026-10-24","vendors":["Linux"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2026-98988/"}