{
  "cvss": 5.5,
  "datePublished": "2026-04-13T14:16:11.907",
  "dateUpdated": "2026-11-05T22:18:30.150",
  "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_flow: fix NULL pointer dereference on shared blocks\n\nflow_change() calls tcf_block_q() and dereferences q->handle to derive\na default baseclass.  Shared blocks leave block->q NULL, causing a NULL\nderef when a flow filter without a fully qualified baseclass is created\non a shared block.\n\nCheck tcf_block_shared() before accessing block->q and return -EINVAL\nfor shared blocks.  This avoids the null-deref shown below:\n\n=======================================================================\nKASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]\nRIP: 0010:flow_change (net/sched/cls_flow.c:508)\nCall Trace:\n tc_new_tfilter (net/sched/cls_api.c:2432)\n rtnetlink_rcv_msg (net/core/rtnetlink.c:6980)\n [...]\n=======================================================================",
  "id": "CVE-2026-31422",
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        "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
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    "cveTags": [],
    "descriptions": [
      {
        "lang": "en",
        "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_flow: fix NULL pointer dereference on shared blocks\n\nflow_change() calls tcf_block_q() and dereferences q->handle to derive\na default baseclass.  Shared blocks leave block->q NULL, causing a NULL\nderef when a flow filter without a fully qualified baseclass is created\non a shared block.\n\nCheck tcf_block_shared() before accessing block->q and return -EINVAL\nfor shared blocks.  This avoids the null-deref shown below:\n\n=======================================================================\nKASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]\nRIP: 0010:flow_change (net/sched/cls_flow.c:508)\nCall Trace:\n tc_new_tfilter (net/sched/cls_api.c:2432)\n rtnetlink_rcv_msg (net/core/rtnetlink.c:6980)\n [...]\n======================================================================="
      }
    ],
    "id": "CVE-2026-31422",
    "lastModified": "2026-11-05T22:18:30.150",
    "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,
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          "source": "nvd@nist.gov",
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                "exploitation": "none"
              },
              {
                "automatable": "no"
              },
              {
                "technicalImpact": "partial"
              }
            ],
            "role": "CISA Coordinator",
            "timestamp": "2026-11-05T21:32:46.390226Z",
            "version": "2.0.3"
          }
        }
      ]
    },
    "published": "2026-04-13T14:16:11.907",
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        "source": "nvd@nist.gov",
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  },
  "severity": "MEDIUM",
  "source": "nvd",
  "title": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_flow: fix NULL pointer dereferenc..."
}