CVE-2026-52980

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-52980", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.376Z", "datePublished": "2026-06-24T16:28:56.457Z", "dateUpdated": "2026-06-24T16:28:56.457Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-06-24T16:28:56.457Z"}, "descriptions": [{"lang": "en", "value": "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->rel_deadline unexpectedly set.\n\nThe failing sequence is:\n\n 1. A task is forked while se->rel_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->rel_deadline is set, place_entity() treats se->deadline\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->vruntime to se->deadline.\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->sum_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->vruntime = se->deadline\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->deadline 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->rel_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."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/sched/core.c"], "versions": [{"version": "82e9d0456e06cebe2c89f3c73cdbc9e3805e9437", "lessThan": "c71bf35caba12bfd9bc23e32b0bcd9e02d1cf1ac", "status": "affected", "versionType": "git"}, {"version": "82e9d0456e06cebe2c89f3c73cdbc9e3805e9437", "lessThan": "f3c16e1f4a314a20717ab90a41885f8111a242ab", "status": "affected", "versionType": "git"}, {"version": "82e9d0456e06cebe2c89f3c73cdbc9e3805e9437", "lessThan": "8f4a16200785f49cf02c5b71bdfe7a9dab63f23a", "status": "affected", "versionType": "git"}, {"version": "82e9d0456e06cebe2c89f3c73cdbc9e3805e9437", "lessThan": "3da56dc063cd77b9c0b40add930767fab4e389f3", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/sched/core.c"], "versions": [{"version": "6.12", "status": "affected"}, {"version": "0", "lessThan": "6.12", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.91", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.33", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0.10", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "6.12.91"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "6.18.33"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "7.0.10"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "7.1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/c71bf35caba12bfd9bc23e32b0bcd9e02d1cf1ac"}, {"url": "https://git.kernel.org/stable/c/f3c16e1f4a314a20717ab90a41885f8111a242ab"}, {"url": "https://git.kernel.org/stable/c/8f4a16200785f49cf02c5b71bdfe7a9dab63f23a"}, {"url": "https://git.kernel.org/stable/c/3da56dc063cd77b9c0b40add930767fab4e389f3"}], "title": "sched/fair: Clear rel_deadline when initializing forked entities", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["kernel/sched/core.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "c71bf35caba12bfd9bc23e32b0bcd9e02d1cf1ac", "status": "affected", "version": "82e9d0456e06cebe2c89f3c73cdbc9e3805e9437", "versionType": "git"}, {"lessThan": "f3c16e1f4a314a20717ab90a41885f8111a242ab", "status": "affected", "version": "82e9d0456e06cebe2c89f3c73cdbc9e3805e9437", "versionType": "git"}, {"lessThan": "8f4a16200785f49cf02c5b71bdfe7a9dab63f23a", "status": "affected", "version": "82e9d0456e06cebe2c89f3c73cdbc9e3805e9437", "versionType": "git"}, {"lessThan": "3da56dc063cd77b9c0b40add930767fab4e389f3", "status": "affected", "version": "82e9d0456e06cebe2c89f3c73cdbc9e3805e9437", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["kernel/sched/core.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.12"}, {"lessThan": "6.12", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.91", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.33", "versionType": "semver"}, {"lessThanOrEqual": "7.0.*", "status": "unaffected", "version": "7.0.10", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "437DB1D8-6045-4090-B868-74ABD26C2E17", "versionEndExcluding": "6.12.91", "versionStartIncluding": "6.12", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "96D99E49-380D-43AB-BDBA-25C3AD018A9C", "versionEndExcluding": "6.18.33", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "A13475D2-59BF-4716-94B5-7C1D239A2CF4", "versionEndExcluding": "7.0.10", "versionStartIncluding": "6.19", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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->rel_deadline unexpectedly set.\n\nThe failing sequence is:\n\n 1. A task is forked while se->rel_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->rel_deadline is set, place_entity() treats se->deadline\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->vruntime to se->deadline.\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->sum_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->vruntime = se->deadline\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->deadline 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->rel_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."}], "id": "CVE-2026-52980", "lastModified": "2026-07-14T16:51:26.420", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2026-06-24T17:17:08.610", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/3da56dc063cd77b9c0b40add930767fab4e389f3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/8f4a16200785f49cf02c5b71bdfe7a9dab63f23a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c71bf35caba12bfd9bc23e32b0bcd9e02d1cf1ac"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f3c16e1f4a314a20717ab90a41885f8111a242ab"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-476"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: sched/fair: Clear rel_deadline when initializing forked entities", "id": "2492340", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492340"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-190", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nsched/fair: Clear rel_deadline when initializing forked entities\nA yield-triggered crash can happen when a newly forked sched_entity\nenters the fair class with se->rel_deadline unexpectedly set.\nThe failing sequence is:\n1. A task is forked while se->rel_deadline is still set.\n2. __sched_fork() initializes vruntime, vlag and other sched_entity\nstate, but does not clear rel_deadline.\n3. On the first enqueue, enqueue_entity() calls place_entity().\n4. Because se->rel_deadline is set, place_entity() treats se->deadline\nas a relative deadline and converts it to an absolute deadline by\nadding the current vruntime.\n5. However, the forked entity's deadline is not a valid inherited\nrelative deadline for this new scheduling instance, so the conversion\nproduces an abnormally large deadline.\n6. If the task later calls sched_yield(), yield_task_fair() advances\nse->vruntime to se->deadline.\n7. The inflated vruntime is then used by the following enqueue path,\nwhere the vruntime-derived key can overflow when multiplied by the\nentity weight.\n8. This corrupts cfs_rq->sum_w_vruntime, breaks EEVDF eligibility\ncalculation, and can eventually make all entities appear ineligible.\npick_next_entity() may then return NULL unexpectedly, leading to a\nlater NULL dereference.\nA captured trace shows the effect clearly. Before yield, the entity's\nvruntime was around:\n9834017729983308\nAfter yield_task_fair() executed:\nse->vruntime = se->deadline\nthe vruntime jumped to:\n19668035460670230\nand the deadline was later advanced further to:\n19668035463470230\nThis shows that the deadline had already become abnormally large before\nyield_task_fair() copied it into vruntime.\nrel_deadline is only meaningful when se->deadline 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->rel_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.", "A flaw was found in the Linux kernel's `sched/fair` scheduler. When a new `sched_entity` is forked, its `rel_deadline` may be unexpectedly set, leading to an abnormally large deadline value. If the task later calls `sched_yield()`, this inflated deadline can cause an overflow in `vruntime` calculations. This can corrupt scheduler data, potentially making all entities appear ineligible and leading to a system crash, resulting in a Denial of Service (DoS)."], "name": "CVE-2026-52980", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-06-24T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-52980\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-52980\nhttps://lore.kernel.org/linux-cve-announce/2026062441-CVE-2026-52980-f55b@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[82e9d0456e06cebe2c89f3c73cdbc9e3805e9437,c71bf35caba12bfd9bc23e32b0bcd9e02d1cf1ac)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[82e9d0456e06cebe2c89f3c73cdbc9e3805e9437,f3c16e1f4a314a20717ab90a41885f8111a242ab)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[82e9d0456e06cebe2c89f3c73cdbc9e3805e9437,8f4a16200785f49cf02c5b71bdfe7a9dab63f23a)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[82e9d0456e06cebe2c89f3c73cdbc9e3805e9437,3da56dc063cd77b9c0b40add930767fab4e389f3)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "6.12"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.12)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.91,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.33,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.0.10,7.1.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-06-24T19:00:06.720008+00:00", "updated": "2026-08-12T06:00:11.042197+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}