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CVE-2016-6828

Status: ModifiedMedium (5.5)—Exploit
Severity5.5Medium · CVSS 3.0
Exploitation probability1.18 %higher than 67% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitAvailablePublished on Exploit-DB

The tcp_check_send_head function in include/net/tcp.h in the Linux kernel before 4.7.5 does not properly maintain certain SACK state after a failed data copy, which allows local users to cause a denial of service (tcp_xmit_retransmit_queue use-after-free and system crash) via a crafted SACK option.

CVSS

Base score
5.5
Version
3.0
Vector
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
1.18 %
Percentile among all scored CVEs
67
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.

Affected technologies (1)

Linux — Linux Kernel

CWEs

References

Show 24 references

Raw JSON (NVD)

Show
{
  "id": "CVE-2016-6828",
  "cveTags": [],
  "metrics": {
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          "vectorString": "AV:L/AC:L/Au:N/C:N/I:N/A:C",
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  "affected": [
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          "versions": [
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  "weaknesses": [
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      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "The tcp_check_send_head function in include/net/tcp.h in the Linux kernel before 4.7.5 does not properly maintain certain SACK state after a failed data copy, which allows local users to cause a denial of service (tcp_xmit_retransmit_queue use-after-free and system crash) via a crafted SACK option."
    },
    {
      "lang": "es",
      "value": "La función tcp_check_send_head en include/net/tcp.h en el kernel de Linux en versiones anteriores a 4.7.5 no mantiene adecuadamente cierto estado SACK tras una copia de datos fallida, lo que permite a usuarios locales provocar una denegación de servicio (uso después de liberación de memoria tcp_xmit_retransmit_queue y caída de sistema ) a través de una opción SACK manipulada."
    }
  ],
  "lastModified": "2026-06-17T00:51:50.920",
  "configurations": [
    {
      "nodes": [
        {
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}