CVE-2023-6606Public exploit

Kernel crash or disclosure via SMB length parsing

Published Dec 8, 2023 · Updated Nov 8, 2025

Out-of-bounds read in the Red Hat Enterprise Linux kernel allows local users to crash the system or read internal kernel data. smbCalcSize trusts an SMB1 header's WordCount when locating the byte-count field, then reads a 16-bit value from that calculated pointer without confirming that the field lies inside the received frame. Low-privileged local access and a loaded CIFS client path are required; exploitation causes a kernel crash or discloses adjacent kernel memory.

CVSS severity7.1
High
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in the Red Hat Enterprise Linux kernel allows local users to crash the system or read internal kernel data. smbCalcSize trusts an SMB1 header's WordCount when locating the byte-count field, then reads a 16-bit value from that calculated pointer without confirming that the field lies inside the received frame. Low-privileged local access and a loaded CIFS client path are required; exploitation causes a kernel crash or discloses adjacent kernel memory.

The record

CVE
CVE-2023-6606
Published
Dec 8, 2023
Updated
Nov 8, 2025
Vendor
Red Hat
Product
Red Hat Enterprise Linux 8
Classifications
CWE-125
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 8, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Red Hat · Red Hat Enterprise Linux 8Affected versions are unavailable in this record.
Red Hat · Red Hat Enterprise Linux 9.2 Extended Update SupportAffected versions are unavailable in this record.
Red Hat · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.
Red Hat · Red Hat Enterprise Linux 8.8 Extended Update SupportAffected versions are unavailable in this record.
Red Hat · Red Hat Enterprise Linux 8.6 Extended Update SupportAffected versions are unavailable in this record.
Red Hat · Red Hat Virtualization 4 for Red Hat Enterprise Linux 8Affected versions are unavailable in this record.

Published CVSS scores

7.1NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
7.1Red HatCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-125Out-of-bounds Read

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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