{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/sched/fair.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5dbe6816c49197677a5ecce749bd99929da147da",
              "status": "affected",
              "version": "152e11f6df293e816a6a37c69757033cdc72667d",
              "versionType": "git"
            },
            {
              "lessThan": "493afbd187c4c9cc1642792c0d9ba400c3d6d90d",
              "status": "affected",
              "version": "152e11f6df293e816a6a37c69757033cdc72667d",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/sched/fair.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": "6.12.7",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.13",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.7",
                  "versionStartIncluding": "6.12",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.13",
                  "versionStartIncluding": "6.12",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/fair: Fix NEXT_BUDDY\n\nAdam reports that enabling NEXT_BUDDY insta triggers a WARN in\npick_next_entity().\n\nMoving clear_buddies() up before the delayed dequeue bits ensures\nno -\u003enext buddy becomes delayed. Further ensure no new -\u003enext buddy\never starts as delayed."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The defect is in the CFS scheduler core (kernel/sched/fair.c), reached by ordinary task wakeup, sleep and load-balancer migration on the local machine. There is no remote or adjacent-network input involved, so an attacker must be able to run code on the system.\nAC:H - The entire bug is gated on the NEXT_BUDDY scheduler feature, which is `SCHED_FEAT(NEXT_BUDDY, false)` \u2014 disabled by default and settable only by root writing /sys/kernel/debug/sched/features on a CONFIG_SCHED_DEBUG=y kernel (sched_feat_write is the sole caller of sched_feat_set; there is no cmdline or sysctl path). An unprivileged attacker cannot create this precondition, and enabling NEXT_BUDDY is rare in practice, so success depends on system state outside the attacker\u0027s control.\nPR:L - Given a system with NEXT_BUDDY enabled, no special capability is needed \u2014 any unprivileged task\u0027s ordinary sleep/wake and the kernel\u0027s own load balancer (attach_task()/move_queued_task() calling wakeup_preempt() on a still-sched_delayed task) drive the code path. Only the ability to run an unprivileged process is required.\nUI:N - No victim action is needed; the reporter observed the WARN triggering instantly on ordinary system activity once the feature was enabled. Normal scheduling and CPU load balancing reach the faulty path on their own.\nS:U - The corrupted state is the kernel\u0027s own per-CPU cfs_rq bookkeeping and sched_entity flags, all within the kernel\u0027s security authority. No VM, IOMMU, or sandbox boundary is crossed.\nC:H - The scheduler is left able to run an entity that is simultaneously marked sched_delayed and blocked, which desynchronizes on_rq/nr_running/load.weight and can drive __dequeue_entity() to rb_erase an already-unlinked node, writing through a stale rb_parent pointer into memory that may have been reused. Such scheduler-structure corruption is leverageable toward reading kernel memory contents.\nI:H - A task in a non-RUNNING state is made to execute \u2014 a direct violation of a core scheduling invariant \u2014 and the resulting sched_delayed/on_rq desync leads to double account_entity_dequeue() (nr_running and load.weight underflow) and rb_erase on an unlinked rbtree node, giving a write primitive over scheduler-adjacent memory rather than a mere miscount.\nA:H - pick_next_entity() fires WARN_ONCE, which is a full kernel panic on the panic_on_warn=1 configurations used by hardened and CI deployments, and further SCHED_WARN_ONs cascade in dequeue_entity()/dequeue_entities(). Beyond the splat, the runqueue accounting underflow and rbtree corruption destabilize scheduling on the affected CPU, causing starvation, hangs, and crashes."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T11:40:03.481Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/5dbe6816c49197677a5ecce749bd99929da147da"
        },
        {
          "url": "https://git.kernel.org/stable/c/493afbd187c4c9cc1642792c0d9ba400c3d6d90d"
        }
      ],
      "title": "sched/fair: Fix NEXT_BUDDY",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2024-49573",
    "datePublished": "2025-01-11T12:35:37.625Z",
    "dateReserved": "2025-01-11T12:32:49.536Z",
    "dateUpdated": "2026-08-05T11:40:03.481Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}