{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-52980 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-52980 is a medium-severity vulnerability in Linux kernel, published on 24 Jun 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-2026-52980 and fix it if it is affected.\n\nWhat it is: CVE-2026-52980 is a medium-severity vulnerability in Linux kernel, published on 24 Jun 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-2026-52980 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-2026-52980/ (Markdown: https://insights.sbomify.com/CVE-2026-52980/index.md)","id":"CVE-2026-52980","markdown":"https://insights.sbomify.com/CVE-2026-52980/index.md","name":"CVE-2026-52980","record":{"aliases":["BELL-CVE-2026-52980","DEBIAN-CVE-2026-52980","GHSA-748m-jm5v-3475","UBUNTU-CVE-2026-52980"],"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 Linux kernel bug in the fair scheduler causes a NULL pointer dereference and system crash when a forked task yields due to uninitialized deadline state.","user_interaction":"not_required","vuln_class":"null_dereference"},"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":[{"id":"CWE-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched/fair: Clear rel_deadline when initializing forked entities\n\nA yield-triggered crash can happen when a newly forked sched_entity\nenters the fair class with se-\u003erel_deadline unexpectedly set.\n\nThe failing sequence is:\n\n  1. A task is forked while se-\u003erel_deadline is still set.\n  2. __sched_fork() initializes vruntime, vlag and other sched_entity\n     state, but does not clear rel_deadline.\n  3. On the first enqueue, enqueue_entity() calls place_entity().\n  4. Because se-\u003erel_deadline is set, place_entity() treats se-\u003edeadline\n     as a relative deadline and converts it to an absolute deadline by\n     adding the current vruntime.\n  5. However, the forked entity's deadline is not a valid inherited\n     relative deadline for this new scheduling instance, so the conversion\n     produces an abnormally large deadline.\n  6. If the task later calls sched_yield(), yield_task_fair() advances\n     se-\u003evruntime to se-\u003edeadline.\n  7. The inflated vruntime is then used by the following enqueue path,\n     where the vruntime-derived key can overflow when multiplied by the\n     entity weight.\n  8. This corrupts cfs_rq-\u003esum_w_vruntime, breaks EEVDF eligibility\n     calculation, and can eventually make all entities appear ineligible.\n     pick_next_entity() may then return NULL unexpectedly, leading to a\n     later NULL dereference.\n\nA captured trace shows the effect clearly. Before yield, the entity's\nvruntime was around:\n\n  9834017729983308\n\nAfter yield_task_fair() executed:\n\n  se-\u003evruntime = se-\u003edeadline\n\nthe vruntime jumped to:\n\n  19668035460670230\n\nand the deadline was later advanced further to:\n\n  19668035463470230\n\nThis shows that the deadline had already become abnormally large before\nyield_task_fair() copied it into vruntime.\n\nrel_deadline is only meaningful when se-\u003edeadline really carries a\nrelative deadline that still needs to be placed against vruntime. A\nfreshly forked sched_entity should not inherit or retain this state.\nClear se-\u003erel_deadline in __sched_fork(), together with the other\nsched_entity runtime state, so that the first enqueue does not interpret\nthe new entity's deadline as a stale relative deadline.","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":"sched/fair: Clear rel_deadline when initializing forked entities","id":"CVE-2026-52980","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2026"},"n_packages":0,"n_references":4,"next":{"headline":"neigh: let neigh_xmit take skb ownership","id":"CVE-2026-52981"},"packages":[],"prev":{"headline":"net: psp: check for device unregister when creating assoc","id":"CVE-2026-52979"},"products":["Linux"],"published":"2026-06-24","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":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-06-24","vendors":["Linux"]},"summary":"A Linux kernel bug in the fair scheduler causes a NULL pointer dereference and system crash when a forked task yields due to uninitialized deadline state.","url":"https://insights.sbomify.com/CVE-2026-52980/"}