{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-74686 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-74686 is a denial of service vulnerability in Linux, published on 22 Aug 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-2026-74686 and fix it if it is affected.\n\nWhat it is: CVE-2026-74686 is a denial of service vulnerability in Linux, published on 22 Aug 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-2026-74686 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-2026-74686/ (Markdown: https://insights.sbomify.com/CVE-2026-74686/index.md)","id":"CVE-2026-74686","markdown":"https://insights.sbomify.com/CVE-2026-74686/index.md","name":"CVE-2026-74686","record":{"aliases":["DEBIAN-CVE-2026-74686","GHSA-fm7x-6qpm-975r","UBUNTU-CVE-2026-74686"],"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":"none","summary":"A flaw in the Linux kernel's rqspinlock implementation can cause indefinite stalls during ABBA deadlock detection, leading to denial of service.","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\nrqspinlock: Reset tail when preserving queue on deadlock\n\nCurrently, the destruction of the waiter queue is suppressed for\nrqspinlock in cases where a deadlock is detected. Deadlock checks happen\nrelatively frequently (on entry for AA, within 1ms for ABBA), and waiter\nthreads may not be involved in locking scenarios involving deadlocks.\nThus, it is useful to not flush the queue and let other waiters take a\nstab at acquiring the lock after we detect a deadlock and exit.\n\nHowever, we need to follow the same logic as what we did previously for\nthe waitq_timeout label: reset the tail, and if we cannot, signal the\nnext waiter appropriately. In case of deadlocks, this signal would just\nmark the MCS node as unlocked, and in case of timeouts, it would signal\nRES_TIMEOUT_VAL. The difference thus is in the value propagated, which\ndecides whether the queue remains active or gets flushed.\n\nNot doing the tail reset, and waiting for the next waiter can lead to\ncases where we are the final waiter, and thus no next waiter arrives,\nleading to intermittent stalls in this path. Once the next waiter does\njoin, we will be unblocked. In the theoretical case when the next waiter\nnever joins, we risk stalling indefinitely.\n\nThis can only happen for ABBA deadlocks, since entry into the wait queue\nis guarded with AA checks. A precise sequence of executions leading up\nto this scenario can be:\n\nCPU 0 holds lock A.\nCPU 1 holds lock B.\nCPU 2 attempts lock B, becomes the pending waiter for B.\nCPU 0 attempts lock B. B has locked+pending bits set, thus CPU 0 queues.\nCPU 1 attempts lock A.\nCPU 0 detects an ABBA deadlock.\n\nOnce deadlock detection happens for CPU 0, it will sit waiting for the\nnext waiter in the queue to populate node-\u003enext, which will experience\ndelays until such a waiter arrives.\n\nFix this by adjusting the logic for the check for deadlocks preceding\nthe waitq_timeout label. It would make sense to consolidate code for\nboth cases and use 'ret' to distinguish the value being propagated, but\nthat is left as an exercise for a future refactoring task to avoid diff\nnoise in this patch.","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":"rqspinlock: Reset tail when preserving queue on deadlock","id":"CVE-2026-74686","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":"watchdog: at91sam9_wdt: prevent timer rearm during teardown","id":"CVE-2026-74687"},"packages":[],"prev":{"headline":"hwmon: (ltc4282) Clamp negative current limits","id":"CVE-2026-74685"},"products":["Linux"],"published":"2026-08-22","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":"2026-08-22","vendors":["Linux"]},"summary":"A flaw in the Linux kernel's rqspinlock implementation can cause indefinite stalls during ABBA deadlock detection, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2026-74686/"}