CVE-2026-99233

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: tracing/histograms: Verify event_call identity when updating synth_event refcount In event_hist_trigger_parse() and hist_unreg_all(), the histogram registration and unregistration paths look up find_synth_event() using trace_event_name(file->event_call) and adjust se->ref if a match is found. Because find_synth_event() only compares the event basename, registering or removing a histogram on a non-synthetic trace event whose basename matches a synthetic event erroneously modifies the synthetic event's reference count. If a histogram is registered on the non-synthetic event before the synthetic event is created and removed afterwards, se->ref is decremented without a matching increment, allowing the synthetic event to be freed while an active histogram action still holds a pointer to it. Introduce find_synth_event_call() to verify that &se->call matches file->event_call before adjusting se->ref.

Severity

HIGH

CVSS score

7.8 (v3.1)

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-11-02 16:17:48.390000

Last modified

2026-11-02 16:17:48.390000

View original CVE JSON

{
  "id": "CVE-2026-99233",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-11-02T16:17:48.390",
  "lastModified": "2026-11-02T16:17:48.390",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntracing/histograms: Verify event_call identity when updating synth_event refcount\n\nIn event_hist_trigger_parse() and hist_unreg_all(), the histogram\nregistration and unregistration paths look up find_synth_event() using\ntrace_event_name(file->event_call) and adjust se->ref if a match is\nfound.\n\nBecause find_synth_event() only compares the event basename, registering\nor removing a histogram on a non-synthetic trace event whose basename\nmatches a synthetic event erroneously modifies the synthetic event's\nreference count.  If a histogram is registered on the non-synthetic\nevent before the synthetic event is created and removed afterwards,\nse->ref is decremented without a matching increment, allowing the\nsynthetic event to be freed while an active histogram action still holds\na pointer to it.\n\nIntroduce find_synth_event_call() to verify that &se->call matches\nfile->event_call before adjusting se->ref."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "kernel/trace/trace_events_hist.c",
            "kernel/trace/trace_events_synth.c",
            "kernel/trace/trace_synth.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "4b147936fa509650beaf638b331573c23ba4d609",
              "lessThan": "381f543ed35c434d5b707369aa5dcd69ecf440af",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4b147936fa509650beaf638b331573c23ba4d609",
              "lessThan": "4472579bd1c83708b6fe623c870cdf728e947205",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4b147936fa509650beaf638b331573c23ba4d609",
              "lessThan": "23b4106e8b35823acc79e206c7745f55b9cfd78b",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4b147936fa509650beaf638b331573c23ba4d609",
              "lessThan": "06e816bed499fe47f39f12044382cc5d064485fb",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4b147936fa509650beaf638b331573c23ba4d609",
              "lessThan": "5597bb8db6855fcb97a67196d227fea359bcd81c",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "4b147936fa509650beaf638b331573c23ba4d609",
              "lessThan": "cf4e31d5da80fae4c9cdbe7af55b7c3ad213f0e4",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "kernel/trace/trace_events_hist.c",
            "kernel/trace/trace_events_synth.c",
            "kernel/trace/trace_synth.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "4.17",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "4.17",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.1.191",
              "lessThanOrEqual": "6.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.161",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.115",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.60",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.14",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3.1",
              "lessThanOrEqual": "7.3.*",
              "versionType": "semver",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 7.8,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 5.9
      }
    ]
  },
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/06e816bed499fe47f39f12044382cc5d064485fb",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/23b4106e8b35823acc79e206c7745f55b9cfd78b",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/381f543ed35c434d5b707369aa5dcd69ecf440af",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/4472579bd1c83708b6fe623c870cdf728e947205",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/5597bb8db6855fcb97a67196d227fea359bcd81c",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/cf4e31d5da80fae4c9cdbe7af55b7c3ad213f0e4",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}