{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-90181 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-90181 is a denial of service vulnerability in Linux, published on 17 Sep 2026. 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-2026-90181 and fix it if it is affected.\n\nWhat it is: CVE-2026-90181 is a denial of service vulnerability in Linux, published on 17 Sep 2026. 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-2026-90181 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-2026-90181/ (Markdown: https://insights.sbomify.com/CVE-2026-90181/index.md)","id":"CVE-2026-90181","markdown":"https://insights.sbomify.com/CVE-2026-90181/index.md","name":"CVE-2026-90181","record":{"aliases":["DEBIAN-CVE-2026-90181","GHSA-6q49-r2pp-pjwc","UBUNTU-CVE-2026-90181"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A local attacker can cause a denial of service in the Linux kernel ublk driver by triggering an infinite retry loop during device teardown when memory allocation fails.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","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\nublk: avoid teardown retry loop on xarray allocation failure\n\n__ublk_shmem_remove_ranges() removes matching maple tree ranges in\nbatches, but first stores each range into a temporary xarray so that the\npages can be unpinned after dropping the maple tree lock.\n\nThat temporary xarray is filled under the maple tree lock with\nxa_store(..., GFP_ATOMIC). If the store fails before mas_erase(), the\ncurrent range is left in the tree and the helper returns false. The\nouter ublk_shmem_remove_ranges() loop then immediately retries the same\nrange. While the atomic allocation keeps failing, the teardown path has\nno forward progress.\n\nThe issue can be reproduced with radix_tree_node failslab injection after\na SHMEM_ZC buffer has already been registered:\n\n  # Kernel config:\n  #   CONFIG_BLK_DEV_UBLK=y\n  #   CONFIG_DEBUG_FS=y\n  #   CONFIG_FAULT_INJECTION=y\n  #   CONFIG_FAULT_INJECTION_DEBUG_FS=y\n  #   CONFIG_FAILSLAB=y\n\n  echo 10 \u003e /proc/sys/vm/nr_hugepages\n  mkdir -p /tmp/htlb\n  mount -t hugetlbfs none /tmp/htlb\n  fallocate -l 4M /tmp/htlb/ublk_buf\n\n  dev_id=$(kublk add -t null --shmem_zc \\\n\t\t--htlb /tmp/htlb/ublk_buf |\n\t   awk -F '[ :]' '/dev id/ {print $3}')\n\n  echo 1 \u003e /sys/kernel/slab/radix_tree_node/failslab\n  echo Y \u003e /sys/kernel/debug/failslab/cache-filter\n  echo Y \u003e /sys/kernel/debug/failslab/ignore-gfp-wait\n  echo 1 \u003e /sys/kernel/debug/failslab/interval\n  echo -1 \u003e /sys/kernel/debug/failslab/times\n  echo 100 \u003e /sys/kernel/debug/failslab/probability\n\n  kublk del -n \"$dev_id\"\n\nOn the unfixed kernel the delete command was still running after 3\nseconds. Disabling failslab made it return. The fault-injection stack\nshowed:\n\n  should_failslab\n  kmem_cache_alloc_lru_noprof\n  __xas_nomem\n  __xa_store\n  xa_store\n  __ublk_shmem_remove_ranges\n  ublk_cdev_rel\n  ublk_ctrl_del_dev\n\nRemove the allocation from the teardown loop. Keep the existing batch\nlimit, but collect {base_pfn, nr_pages} pairs in a fixed-size stack array.\nOnce a matching range is found, the range is erased from the maple tree\nbefore dropping the lock, so each successful scan makes progress without\ndepending on any GFP_ATOMIC allocation.\n\nWith the same failslab settings, the fixed kernel completed\n\"kublk del -n $dev_id\" successfully in about 45 ms.","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":"ublk: avoid teardown retry loop on xarray allocation failure","id":"CVE-2026-90181","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"blk-iocost: clear delay state when freeing policy data","id":"CVE-2026-90182"},"packages":[],"prev":{"headline":"block: mtip32xx: synchronize ioctls with device removal","id":"CVE-2026-90180"},"products":["Linux"],"published":"2026-09-17","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":"2026-10-19","vendors":["Linux"]},"summary":"A local attacker can cause a denial of service in the Linux kernel ublk driver by triggering an infinite retry loop during device teardown when memory allocation fails.","url":"https://insights.sbomify.com/CVE-2026-90181/"}