{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-31465 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-31465 is a medium-severity denial of service vulnerability in Linux kernel, published on 22 Apr 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-2026-31465 and fix it if it is affected.\n\nWhat it is: CVE-2026-31465 is a medium-severity denial of service vulnerability in Linux kernel, published on 22 Apr 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-2026-31465 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-2026-31465/ (Markdown: https://insights.sbomify.com/CVE-2026-31465/index.md)","id":"CVE-2026-31465","markdown":"https://insights.sbomify.com/CVE-2026-31465/index.md","name":"CVE-2026-31465","record":{"aliases":["BELL-CVE-2026-31465","DEBIAN-CVE-2026-31465","GHSA-3wmh-pgp5-9q7q","UBUNTU-CVE-2026-31465"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A flaw in the Linux kernel writeback mechanism causes system hangs during suspend when using filesystems without data integrity guarantees, such as FUSE.","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":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nwriteback: don't block sync for filesystems with no data integrity guarantees\n\nAdd a SB_I_NO_DATA_INTEGRITY superblock flag for filesystems that cannot\nguarantee data persistence on sync (eg fuse). For superblocks with this\nflag set, sync kicks off writeback of dirty inodes but does not wait\nfor the flusher threads to complete the writeback.\n\nThis replaces the per-inode AS_NO_DATA_INTEGRITY mapping flag added in\ncommit f9a49aa302a0 (\"fs/writeback: skip AS_NO_DATA_INTEGRITY mappings\nin wait_sb_inodes()\"). The flag belongs at the superblock level because\ndata integrity is a filesystem-wide property, not a per-inode one.\nHaving this flag at the superblock level also allows us to skip having\nto iterate every dirty inode in wait_sb_inodes() only to skip each inode\nindividually.\n\nPrior to this commit, mappings with no data integrity guarantees skipped\nwaiting on writeback completion but still waited on the flusher threads\nto finish initiating the writeback. Waiting on the flusher threads is\nunnecessary. This commit kicks off writeback but does not wait on the\nflusher threads. This change properly addresses a recent report [1] for\na suspend-to-RAM hang seen on fuse-overlayfs that was caused by waiting\non the flusher threads to finish:\n\nWorkqueue: pm_fs_sync pm_fs_sync_work_fn\nCall Trace:\n \u003cTASK\u003e\n __schedule+0x457/0x1720\n schedule+0x27/0xd0\n wb_wait_for_completion+0x97/0xe0\n sync_inodes_sb+0xf8/0x2e0\n __iterate_supers+0xdc/0x160\n ksys_sync+0x43/0xb0\n pm_fs_sync_work_fn+0x17/0xa0\n process_one_work+0x193/0x350\n worker_thread+0x1a1/0x310\n kthread+0xfc/0x240\n ret_from_fork+0x243/0x280\n ret_from_fork_asm+0x1a/0x30\n \u003c/TASK\u003e\n\nOn fuse this is problematic because there are paths that may cause the\nflusher thread to block (eg if systemd freezes the user session cgroups\nfirst, which freezes the fuse daemon, before invoking the kernel\nsuspend. The kernel suspend triggers -\u003ewrite_node() which on fuse issues\na synchronous setattr request, which cannot be processed since the\ndaemon is frozen. Or if the daemon is buggy and cannot properly complete\nwriteback, initiating writeback on a dirty folio already under writeback\nleads to writeback_get_folio() -\u003e folio_prepare_writeback() -\u003e\nunconditional wait on writeback to finish, which will cause a hang).\nThis commit restores fuse to its prior behavior before tmp folios were\nremoved, where sync was essentially a no-op.\n\n[1] https://lore.kernel.org/linux-fsdevel/CAJnrk1a-asuvfrbKXbEwwDSctvemF+6zfhdnuzO65Pt8HsFSRw@mail.gmail.com/T/#m632c4648e9cafc4239299887109ebd880ac6c5c1","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":"writeback: don't block sync for filesystems with no data integrity guarantees","id":"CVE-2026-31465","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":3,"next":{"headline":"mm/huge_memory: fix folio isn't locked in softleaf_to_folio()","id":"CVE-2026-31466"},"packages":[],"prev":{"headline":"scsi: ibmvfc: Fix OOB access in ibmvfc_discover_targets_done()","id":"CVE-2026-31464"},"products":["Linux"],"published":"2026-04-22","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":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A flaw in the Linux kernel writeback mechanism causes system hangs during suspend when using filesystems without data integrity guarantees, such as FUSE.","url":"https://insights.sbomify.com/CVE-2026-31465/"}