{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.85-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.19.11-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  mm/damon/sysfs: check contexts-\u003enr before accessing contexts_arr[0]  Multiple sysfs command paths dereference contexts_arr[0] without first verifying that kdamond-\u003econtexts-\u003enr == 1.  A user can set nr_contexts to 0 via sysfs while DAMON is running, causing NULL pointer dereferences.  In more detail, the issue can be triggered by privileged users like below.  First, start DAMON and make contexts directory empty (kdamond-\u003econtexts-\u003enr == 0).      # damo start     # cd /sys/kernel/mm/damon/admin/kdamonds/0     # echo 0 \u003e contexts/nr_contexts  Then, each of below commands will cause the NULL pointer dereference.      # echo update_schemes_stats \u003e state     # echo update_schemes_tried_regions \u003e state     # echo update_schemes_tried_bytes \u003e state     # echo update_schemes_effective_quotas \u003e state     # echo update_tuned_intervals \u003e state  Guard all commands (except OFF) at the entry point of damon_sysfs_handle_cmd().",
  "id": "DEBIAN-CVE-2026-31458",
  "modified": "2026-09-14T16:47:33.145577297Z",
  "published": "2026-04-22T14:16:41.260Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-31458"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-31458"
  ]
}