{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/sched/sch_hfsc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "28b09a067831f7317c3841812276022d6c940677",
              "status": "affected",
              "version": "21f4d5cc25ec0e6e8eb8420dd2c399e6d2fc7d14",
              "versionType": "git"
            },
            {
              "lessThan": "39b9095dd3b55d9b2743df038c32138efa34a9de",
              "status": "affected",
              "version": "21f4d5cc25ec0e6e8eb8420dd2c399e6d2fc7d14",
              "versionType": "git"
            },
            {
              "lessThan": "fcc8ede663569c704fb00a702973bd6c00373283",
              "status": "affected",
              "version": "21f4d5cc25ec0e6e8eb8420dd2c399e6d2fc7d14",
              "versionType": "git"
            },
            {
              "lessThan": "20d584a33e480ae80d105f43e0e7b56784da41b9",
              "status": "affected",
              "version": "21f4d5cc25ec0e6e8eb8420dd2c399e6d2fc7d14",
              "versionType": "git"
            },
            {
              "lessThan": "3aa852e3605000d5c47035c3fc3a986d14ccfa9f",
              "status": "affected",
              "version": "21f4d5cc25ec0e6e8eb8420dd2c399e6d2fc7d14",
              "versionType": "git"
            },
            {
              "lessThan": "86cd4641c713455a4f1c8e54c370c598c2b1cee0",
              "status": "affected",
              "version": "21f4d5cc25ec0e6e8eb8420dd2c399e6d2fc7d14",
              "versionType": "git"
            },
            {
              "lessThan": "bb583c88d23b72d8d16453d24856c99bd93dadf5",
              "status": "affected",
              "version": "21f4d5cc25ec0e6e8eb8420dd2c399e6d2fc7d14",
              "versionType": "git"
            },
            {
              "lessThan": "3df275ef0a6ae181e8428a6589ef5d5231e58b5c",
              "status": "affected",
              "version": "21f4d5cc25ec0e6e8eb8420dd2c399e6d2fc7d14",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/sched/sch_hfsc.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "4.14"
            },
            {
              "lessThan": "4.14",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.4.*",
              "status": "unaffected",
              "version": "5.4.293",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.237",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.181",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.136",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.89",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.26",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.14.*",
              "status": "unaffected",
              "version": "6.14.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.15-rc4",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet_sched: hfsc: Fix a UAF vulnerability in class handling\n\nThis patch fixes a Use-After-Free vulnerability in the HFSC qdisc class\nhandling. The issue occurs due to a time-of-check/time-of-use condition\nin hfsc_change_class() when working with certain child qdiscs like netem\nor codel.\n\nThe vulnerability works as follows:\n1. hfsc_change_class() checks if a class has packets (q.qlen != 0)\n2. It then calls qdisc_peek_len(), which for certain qdiscs (e.g.,\n   codel, netem) might drop packets and empty the queue\n3. The code continues assuming the queue is still non-empty, adding\n   the class to vttree\n4. This breaks HFSC scheduler assumptions that only non-empty classes\n   are in vttree\n5. Later, when the class is destroyed, this can lead to a Use-After-Free\n\nThe fix adds a second queue length check after qdisc_peek_len() to verify\nthe queue wasn\u0027t emptied."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-05-02T14:16:01.905Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/28b09a067831f7317c3841812276022d6c940677"
        },
        {
          "url": "https://git.kernel.org/stable/c/39b9095dd3b55d9b2743df038c32138efa34a9de"
        },
        {
          "url": "https://git.kernel.org/stable/c/fcc8ede663569c704fb00a702973bd6c00373283"
        },
        {
          "url": "https://git.kernel.org/stable/c/20d584a33e480ae80d105f43e0e7b56784da41b9"
        },
        {
          "url": "https://git.kernel.org/stable/c/3aa852e3605000d5c47035c3fc3a986d14ccfa9f"
        },
        {
          "url": "https://git.kernel.org/stable/c/86cd4641c713455a4f1c8e54c370c598c2b1cee0"
        },
        {
          "url": "https://git.kernel.org/stable/c/bb583c88d23b72d8d16453d24856c99bd93dadf5"
        },
        {
          "url": "https://git.kernel.org/stable/c/3df275ef0a6ae181e8428a6589ef5d5231e58b5c"
        }
      ],
      "title": "net_sched: hfsc: Fix a UAF vulnerability in class handling",
      "x_generator": {
        "engine": "bippy-1.1.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-37797",
    "datePublished": "2025-05-02T14:16:01.905Z",
    "dateReserved": "2025-04-16T04:51:23.941Z",
    "dateUpdated": "2025-05-02T14:16:01.905Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-37797\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-05-02T15:15:48.557\",\"lastModified\":\"2025-05-02T15:15:48.557\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nnet_sched: hfsc: Fix a UAF vulnerability in class handling\\n\\nThis patch fixes a Use-After-Free vulnerability in the HFSC qdisc class\\nhandling. The issue occurs due to a time-of-check/time-of-use condition\\nin hfsc_change_class() when working with certain child qdiscs like netem\\nor codel.\\n\\nThe vulnerability works as follows:\\n1. hfsc_change_class() checks if a class has packets (q.qlen != 0)\\n2. It then calls qdisc_peek_len(), which for certain qdiscs (e.g.,\\n   codel, netem) might drop packets and empty the queue\\n3. The code continues assuming the queue is still non-empty, adding\\n   the class to vttree\\n4. This breaks HFSC scheduler assumptions that only non-empty classes\\n   are in vttree\\n5. Later, when the class is destroyed, this can lead to a Use-After-Free\\n\\nThe fix adds a second queue length check after qdisc_peek_len() to verify\\nthe queue wasn\u0027t emptied.\"}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/20d584a33e480ae80d105f43e0e7b56784da41b9\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/28b09a067831f7317c3841812276022d6c940677\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/39b9095dd3b55d9b2743df038c32138efa34a9de\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3aa852e3605000d5c47035c3fc3a986d14ccfa9f\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/3df275ef0a6ae181e8428a6589ef5d5231e58b5c\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/86cd4641c713455a4f1c8e54c370c598c2b1cee0\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/bb583c88d23b72d8d16453d24856c99bd93dadf5\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/fcc8ede663569c704fb00a702973bd6c00373283\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
  }
}