FKIE_CVE-2026-31422

Vulnerability from fkie_nvd - Published: 2026-04-13 14:16 - Updated: 2026-05-20 18:08
Severity
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_flow: fix NULL pointer dereference on shared blocks flow_change() calls tcf_block_q() and dereferences q->handle to derive a default baseclass. Shared blocks leave block->q NULL, causing a NULL deref when a flow filter without a fully qualified baseclass is created on a shared block. Check tcf_block_shared() before accessing block->q and return -EINVAL for shared blocks. This avoids the null-deref shown below: ======================================================================= KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] RIP: 0010:flow_change (net/sched/cls_flow.c:508) Call Trace: tc_new_tfilter (net/sched/cls_api.c:2432) rtnetlink_rcv_msg (net/core/rtnetlink.c:6980) [...] =======================================================================
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1a280dd4bd1d616a01d6ffe0de284c907b555504Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/415ea0c973c754b9f375225807810eb9045f4293Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/4a09f72007201c9f667dc47f64517ec23eea65e5Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/57f94ac7e953eece5ed4819605a18f3cdfc63dccPatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/942813276edeb1741fa5b0a73471beb4e495fa08Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/9bf5fc36a43f7b8b5507c96e74fb81f1e8b4957ePatch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a208c3e1232997e9317887294c20008dfcb75449Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/cc707a4fd4c3b6ab2722e06bc359aa010e13d408Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
linux linux_kernel 7.0
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      "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-\u003ehandle to derive\na default baseclass.  Shared blocks leave block-\u003eq 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-\u003eq 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======================================================================="
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  "id": "CVE-2026-31422",
  "lastModified": "2026-05-20T18:08:43.857",
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          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
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  "published": "2026-04-13T14:16:11.907",
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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