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FKIE_CVE-2026-74290

Vulnerability from fkie_nvd - Published: 2026-08-15 06:22 - Updated: 2026-08-17 06:19
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_flow: Dont expose folded kernel pointers The flow classifier falls back to addr_fold() for fields that are missing from packet headers. In map mode, userspace controls mask, xor, rshift, addend and divisor, and can observe the resulting classid through class statistics. This allows a tc classifier in a user/network namespace to recover the 32-bit folded value of skb->sk, skb_dst() or skb_nfct(). Align with standard kernel practices for pointer hashing and replace the XOR folding with a keyed siphash (which is cryptographically secure)
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/0a8b5b74f0e6b6b9ce453bcfa4baa502c4c7577a
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/19f2ecf8ea564562c7e7a919cf38068dd9aa1c96
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/3d054001860270748405a3f9270c5fa0bf7ffc19
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6151159618198675e01c391676e579738286c135
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f294fc71c4a0fa4964f6428a1b4e7929c1d83125
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/fb31fbe51c233f3bf47021121f63d2e42cac2d08
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sched/cls_flow.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "19f2ecf8ea564562c7e7a919cf38068dd9aa1c96",
              "status": "affected",
              "version": "e5dfb815181fcb186d6080ac3a091eadff2d98fe",
              "versionType": "git"
            },
            {
              "lessThan": "3d054001860270748405a3f9270c5fa0bf7ffc19",
              "status": "affected",
              "version": "e5dfb815181fcb186d6080ac3a091eadff2d98fe",
              "versionType": "git"
            },
            {
              "lessThan": "fb31fbe51c233f3bf47021121f63d2e42cac2d08",
              "status": "affected",
              "version": "e5dfb815181fcb186d6080ac3a091eadff2d98fe",
              "versionType": "git"
            },
            {
              "lessThan": "0a8b5b74f0e6b6b9ce453bcfa4baa502c4c7577a",
              "status": "affected",
              "version": "e5dfb815181fcb186d6080ac3a091eadff2d98fe",
              "versionType": "git"
            },
            {
              "lessThan": "6151159618198675e01c391676e579738286c135",
              "status": "affected",
              "version": "e5dfb815181fcb186d6080ac3a091eadff2d98fe",
              "versionType": "git"
            },
            {
              "lessThan": "f294fc71c4a0fa4964f6428a1b4e7929c1d83125",
              "status": "affected",
              "version": "e5dfb815181fcb186d6080ac3a091eadff2d98fe",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sched/cls_flow.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "2.6.25"
            },
            {
              "lessThan": "2.6.25",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.178",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: cls_flow: Dont expose folded kernel pointers\n\nThe flow classifier falls back to addr_fold() for fields that are missing\nfrom packet headers. In map mode, userspace controls mask, xor, rshift,\naddend and divisor, and can observe the resulting classid through class\nstatistics. This allows a tc classifier in a user/network namespace to\nrecover the 32-bit folded value of skb-\u003esk, skb_dst() or skb_nfct().\n\nAlign with standard kernel practices for pointer hashing and replace the\nXOR folding with a keyed siphash (which is cryptographically secure)"
    }
  ],
  "id": "CVE-2026-74290",
  "lastModified": "2026-08-17T06:19:22.973",
  "metrics": {},
  "published": "2026-08-15T06:22:28.570",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0a8b5b74f0e6b6b9ce453bcfa4baa502c4c7577a"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/19f2ecf8ea564562c7e7a919cf38068dd9aa1c96"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3d054001860270748405a3f9270c5fa0bf7ffc19"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/6151159618198675e01c391676e579738286c135"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/f294fc71c4a0fa4964f6428a1b4e7929c1d83125"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/fb31fbe51c233f3bf47021121f63d2e42cac2d08"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}



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