{
  "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"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.2.8-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  net/sched: codel: bound the dropping loop per dequeue call  The CoDel control law schedules the next drop one interval/sqrt(count) after the previous drop, using the configured interval (codel_params.interval). For very small intervals the scheduled step rounds down to zero, so the dropping loop in codel_dequeue() never advances and drains the entire backlog under the qdisc lock in one call - an unprivileged user can trigger a soft lockup this way.  Fix in the shared codel code used by both codel and fq_codel:  1. Make the control-law step at least 1 tick so the dropping loop    always moves forward.  2. Cap the dropping loop at CODEL_MAX_DROPS_PER_DEQUEUE (256) drops    per codel_dequeue() call, resyncing drop_next to now when the cap    is hit: the catch-up owed to the loop grows with the idle gap and    the backlog, which no interval threshold can bound. This is a    deliberate behaviour change after long idle gaps.  The cap applies to fq_codel (4b549a2ef4be) and the mac80211 TXQ path (fixed interval, cap only).  The target sojourn delay (codel_params.target) is not validated: it does not feed the control law, so a sub-tick value is aggressive rather than deadlock-prone.  Conditions to recreate the bug:   - tc qdisc add dev lo root handle 1: tbf rate 1kbit burst 2kb limit 1000000   - tc qdisc add dev lo parent 1:1 handle 10: codel interval 2us target 1ms noecn limit 1000000 (same for fq_codel)   - unpatched kernel: tc accepts it; a UDP flood under the 1kbit tbf     soft-lockups (watchdog: BUG: soft lockup) while one     codel_dequeue() call drops the backlog under the qdisc lock   - patched kernel: same setup, at most 256 drops per dequeue call,     no soft lockup  Testing: claim reproducer and interval 2us/3us variants run clean; tdc qdisc category passes (see the selftests patch).",
  "id": "DEBIAN-CVE-2026-98427",
  "modified": "2026-10-15T04:47:25.386255529Z",
  "published": "2026-10-14T14:17:54.343Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-98427"
    }
  ],
  "upstream": [
    "CVE-2026-98427"
  ]
}