{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "10239edf86f137ce4c39b62ea9575e8053c549a0"
            },
            {
              "fixed": "7adfd0a42174b85c6bd678858ecd6674f403f336"
            },
            {
              "fixed": "35fd423a5c5132c6f4321f6c4f0a7b4b90af830c"
            },
            {
              "fixed": "06d2a101e89063cb0b9b459104db48bdfb0a797d"
            },
            {
              "fixed": "d8e2f1f0263b7c97b222c06070cccf13e0ab7112"
            },
            {
              "fixed": "f3f4a5cb4a6e9b1f1f25d34dfc25f836a1601db4"
            },
            {
              "fixed": "1731ff1d20489afe4cd01b7d16d37f324746ac54"
            },
            {
              "fixed": "f6547d27ce2093c5627636fb63dd0b7523c466f9"
            },
            {
              "fixed": "2cef2588c995722a901368def30befeef9ae55c6"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.14.0"
            },
            {
              "fixed": "5.10.271"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.222"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.189"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.158"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.112"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.54"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98234.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: hhf: cap hh_flows_limit at change time\n\nhhf_change() stores TCA_HHF_HH_FLOWS_LIMIT with no upper bound. A huge\nhh_flows_limit lets each new heavy-hitter flow pass the\nhh_flows_current_cnt check in alloc_new_hh() and forces a fixed-size\nkzalloc(GFP_ATOMIC) per flow under spoofed traffic, for unbounded memory\ngrowth.\n\nBound the attribute with NLA_POLICY_MAX() at 2*HH_FLOWS_CNT (the\nhhf_init() default) and report the rejected value via extack. The\ndeprecated nested parse is kept: legacy tc does not set NLA_F_NESTED on\nTCA_OPTIONS. Configs relying on hh_limit above the default were relying\non unbounded, unsafe behaviour and are not supported going forward.\n\nhhf_init() also ran hhf_change() before setting the default\nhh_flows_limit, so a user-supplied hh_limit at add time was clobbered\nback to 2048. Set the default before hhf_change() so the configured\nvalue sticks.\n\nThis is a follow-up to commit eb56a495f59b (\"net/sched: hhf: clamp\nquantum in change and init paths\"), which bounded the quantum of the\nsame qdisc; the hh_flows_limit bound is the remaining unbounded knob of\nthat series' scope.\n\nConditions to recreate the bug: CAP_NET_ADMIN in a user namespace;\ntc qdisc change dev X root hhf hh_limit 4294967295 succeeds and the\nvalue is echoed by tc qdisc show, unbounding heavy-hitter flow\nallocations; also tc qdisc add dev X root hhf hh_limit 500 stores 2048\ninstead of 500.",
  "id": "CVE-2026-98234",
  "modified": "2026-10-08T02:30:56.954525131Z",
  "published": "2026-10-06T08:45:07.215Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/06d2a101e89063cb0b9b459104db48bdfb0a797d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/1731ff1d20489afe4cd01b7d16d37f324746ac54"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2cef2588c995722a901368def30befeef9ae55c6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/35fd423a5c5132c6f4321f6c4f0a7b4b90af830c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7adfd0a42174b85c6bd678858ecd6674f403f336"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d8e2f1f0263b7c97b222c06070cccf13e0ab7112"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f3f4a5cb4a6e9b1f1f25d34dfc25f836a1601db4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f6547d27ce2093c5627636fb63dd0b7523c466f9"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98234.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98234"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "net/sched: hhf: cap hh_flows_limit at change time"
}