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CVE-2016-6516

Status: ModifiedHigh (7.4)—PoC
Severity7.4High · CVSS 3.0
Exploitation probability0.95 %higher than 61% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitAvailableProof of concept on GitHub (unverified)

Race condition in the ioctl_file_dedupe_range function in fs/ioctl.c in the Linux kernel through 4.7 allows local users to cause a denial of service (heap-based buffer overflow) or possibly gain privileges by changing a certain count value, aka a "double fetch" vulnerability.

CVSS

Base score
7.4
Version
3.0
Vector
CVSS:3.0/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
0.95 %
Percentile among all scored CVEs
61
Score date
10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

Affected technologies (1)

Linux — Linux Kernel

CWEs

References

Show 10 references

Raw JSON (NVD)

Show
{
  "id": "CVE-2016-6516",
  "cveTags": [],
  "metrics": {
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "description": [
        {
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          "value": "CWE-119"
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    {
      "lang": "en",
      "value": "Race condition in the ioctl_file_dedupe_range function in fs/ioctl.c in the Linux kernel through 4.7 allows local users to cause a denial of service (heap-based buffer overflow) or possibly gain privileges by changing a certain count value, aka a \"double fetch\" vulnerability."
    },
    {
      "lang": "es",
      "value": "Condición de carrera en la función ioctl_file_dedupe_range en fs/ioctl.c en el kernel de Linux hasta la versión 4.7 permite a usuarios locales provocar una denegación de servicio (desbordamiento de búfer basado en memoria dinámica) o posiblemente obtener privilegios cambiando un cierto valor de recuento, también conocido como una vulnerabilidad de \"doble recuperación\"."
    }
  ],
  "lastModified": "2026-06-17T00:51:18.483",
  "configurations": [
    {
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              "versionEndIncluding": "4.7"
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  "sourceIdentifier": "cve@mitre.org"
}