CVE-2026-31675 (GCVE-0-2026-31675)
Vulnerability from cvelistv5
Published
2026-04-25 08:46
Modified
2026-04-27 14:04
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_netem: fix out-of-bounds access in packet corruption In netem_enqueue(), the packet corruption logic uses get_random_u32_below(skb_headlen(skb)) to select an index for modifying skb->data. When an AF_PACKET TX_RING sends fully non-linear packets over an IPIP tunnel, skb_headlen(skb) evaluates to 0. Passing 0 to get_random_u32_below() takes the variable-ceil slow path which returns an unconstrained 32-bit random integer. Using this unconstrained value as an offset into skb->data results in an out-of-bounds memory access. Fix this by verifying skb_headlen(skb) is non-zero before attempting to corrupt the linear data area. Fully non-linear packets will silently bypass the corruption logic.
References
Impacted products
Vendor Product Version
Linux Linux Version: c865e5d99e25a171e8262fc0f7ba608568633c64
Version: c865e5d99e25a171e8262fc0f7ba608568633c64
Version: c865e5d99e25a171e8262fc0f7ba608568633c64
Version: c865e5d99e25a171e8262fc0f7ba608568633c64
Version: c865e5d99e25a171e8262fc0f7ba608568633c64
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{
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          "programFiles": [
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      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
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              "negate": false,
              "operator": "OR"
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_netem: fix out-of-bounds access in packet corruption\n\nIn netem_enqueue(), the packet corruption logic uses\nget_random_u32_below(skb_headlen(skb)) to select an index for\nmodifying skb-\u003edata. When an AF_PACKET TX_RING sends fully non-linear\npackets over an IPIP tunnel, skb_headlen(skb) evaluates to 0.\n\nPassing 0 to get_random_u32_below() takes the variable-ceil slow path\nwhich returns an unconstrained 32-bit random integer. Using this\nunconstrained value as an offset into skb-\u003edata results in an\nout-of-bounds memory access.\n\nFix this by verifying skb_headlen(skb) is non-zero before attempting\nto corrupt the linear data area. Fully non-linear packets will silently\nbypass the corruption logic."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
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      "providerMetadata": {
        "dateUpdated": "2026-04-27T14:04:56.555Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/a14b56863348686dd0387eea8ce66b85cf455908"
        },
        {
          "url": "https://git.kernel.org/stable/c/13a66ca1e235d4bcd53d12d4c68490cad7f8e46f"
        },
        {
          "url": "https://git.kernel.org/stable/c/3a2999704ac36cfb4041fed3652d26a3373e8d12"
        },
        {
          "url": "https://git.kernel.org/stable/c/4fd258e281fa8bc15e9ce2c7691941537e9258ad"
        },
        {
          "url": "https://git.kernel.org/stable/c/d64cb81dcbd54927515a7f65e5e24affdc73c14b"
        }
      ],
      "title": "net/sched: sch_netem: fix out-of-bounds access in packet corruption",
      "x_generator": {
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  "cveMetadata": {
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31675",
    "datePublished": "2026-04-25T08:46:51.184Z",
    "dateReserved": "2026-03-09T15:48:24.130Z",
    "dateUpdated": "2026-04-27T14:04:56.555Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


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