CVE-2023-3866

HIGHEPSS 95th pctl

7.5

CVSS v3

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate session id and tree id in the compound request This patch validate session id and tree id in compound request. If first operation in the compound is SMB2 ECHO request, ksmbd bypass session and tree validation. So work->sess and work->tcon could be NULL. If secound request in the compound access work->sess or tcon, It cause NULL pointer dereferecing error.

CWE-476NULL Pointer Dereference

How to fix

Remediation Available

linuxDebian

Fixed in:6.1.37-1CVE-2023-3866

Fixed in:6.3.11-1CVE-2023-3866

linuxUbuntu

Fixed in:5.15.0-86.96USN-6416-1

Fixed in:6.2.0-36.37USN-6464-1

linux-awsUbuntu

Fixed in:5.15.0-1047.52USN-6416-1

Fixed in:6.2.0-1015.15USN-6464-1

linux-aws-5.15Ubuntu

Fixed in:5.15.0-1047.52~20.04.1USN-6416-1

linux-aws-6.2Ubuntu

Fixed in:6.2.0-1015.15~22.04.1USN-6464-1

linux-azureUbuntu

Fixed in:5.15.0-1049.56USN-6416-1

Fixed in:6.2.0-1016.16USN-6464-1

linux-azure-5.15Ubuntu

Fixed in:5.15.0-1049.56~20.04.1USN-6416-1

linux-azure-6.2Ubuntu

Fixed in:6.2.0-1016.16~22.04.1USN-6464-1

linux-azure-fdeUbuntu

Fixed in:5.15.0-1049.56.1USN-6416-1

linux-azure-fde-5.15Ubuntu

Fixed in:5.15.0-1049.56~20.04.1.1USN-6416-1

linux-azure-fde-6.2Ubuntu

Fixed in:6.2.0-1016.16~22.04.1.1USN-6464-1

linux-gcpUbuntu

Fixed in:5.15.0-1044.52USN-6416-1

Fixed in:6.2.0-1018.20USN-6464-1

linux-gcp-5.15Ubuntu

Fixed in:5.15.0-1044.52~20.04.1USN-6416-1

linux-gcp-6.2Ubuntu

Fixed in:6.2.0-1018.20~22.04.1USN-6464-1

linux-gkeUbuntu

Fixed in:5.15.0-1044.49USN-6416-1

linux-gkeopUbuntu

Fixed in:5.15.0-1030.35USN-6416-1

linux-gkeop-5.15Ubuntu

Fixed in:5.15.0-1030.35~20.04.1USN-6416-1

linux-hwe-5.15Ubuntu

Fixed in:5.15.0-86.96~20.04.1USN-6416-2

linux-hwe-6.2Ubuntu

Fixed in:6.2.0-36.37~22.04.1USN-6464-1

linux-ibmUbuntu

Fixed in:5.15.0-1040.43USN-6416-1

linux-ibm-5.15Ubuntu

Fixed in:5.15.0-1040.43~20.04.1USN-6416-1

linux-image-5.15.0-1030-gkeopUbuntu

Fixed in:5.15.0-1030.35~20.04.1USN-6416-1

Fixed in:5.15.0-1030.35USN-6416-1

linux-image-5.15.0-1037-nvidiaUbuntu

Fixed in:5.15.0-1037.37USN-6416-1

linux-image-5.15.0-1037-nvidia-lowlatencyUbuntu

Fixed in:5.15.0-1037.37USN-6416-1

linux-image-5.15.0-1040-ibmUbuntu

Fixed in:5.15.0-1040.43~20.04.1USN-6416-1

Fixed in:5.15.0-1040.43USN-6416-1

linux-image-5.15.0-1040-raspiUbuntu

Fixed in:5.15.0-1040.43USN-6416-3

linux-image-5.15.0-1043-intel-iotgUbuntu

Fixed in:5.15.0-1043.49~20.04.1USN-6445-2

Fixed in:5.15.0-1043.49USN-6445-1

linux-image-5.15.0-1044-gcpUbuntu

Fixed in:5.15.0-1044.52~20.04.1USN-6416-1

Fixed in:5.15.0-1044.52USN-6416-1

linux-image-5.15.0-1044-gkeUbuntu

Fixed in:5.15.0-1044.49USN-6416-1

linux-image-5.15.0-1044-kvmUbuntu

Fixed in:5.15.0-1044.49USN-6416-1

linux-image-5.15.0-1045-oracleUbuntu

Fixed in:5.15.0-1045.51~20.04.1USN-6416-2

Fixed in:5.15.0-1045.51USN-6416-1

linux-image-5.15.0-1047-awsUbuntu

Fixed in:5.15.0-1047.52~20.04.1USN-6416-1

Fixed in:5.15.0-1047.52USN-6416-1

linux-image-5.15.0-1049-azureUbuntu

Fixed in:5.15.0-1049.56~20.04.1USN-6416-1

Fixed in:5.15.0-1049.56USN-6416-1

linux-image-5.15.0-1049-azure-fdeUbuntu

Fixed in:5.15.0-1049.56~20.04.1.1USN-6416-1

Fixed in:5.15.0-1049.56.1USN-6416-1

linux-image-5.15.0-86-genericUbuntu

Fixed in:5.15.0-86.96~20.04.1USN-6416-2

Fixed in:5.15.0-86.96USN-6416-1

linux-image-5.15.0-86-generic-64kUbuntu

Fixed in:5.15.0-86.96~20.04.1USN-6416-2

Fixed in:5.15.0-86.96USN-6416-1

linux-image-5.15.0-86-generic-lpaeUbuntu

Fixed in:5.15.0-86.96~20.04.1USN-6416-2

Fixed in:5.15.0-86.96USN-6416-1

linux-image-5.15.0-86-lowlatencyUbuntu

Fixed in:5.15.0-86.95~20.04.1USN-6416-1

Fixed in:5.15.0-86.95USN-6416-1

linux-image-5.15.0-86-lowlatency-64kUbuntu

Fixed in:5.15.0-86.95~20.04.1USN-6416-1

Fixed in:5.15.0-86.95USN-6416-1

linux-image-6.2.0-1008-starfiveUbuntu

Fixed in:6.2.0-1008.9USN-6464-1

linux-image-6.2.0-1009-starfiveUbuntu

Fixed in:6.2.0-1009.10~22.04.1USN-6520-1

linux-image-6.2.0-1011-nvidiaUbuntu

Fixed in:6.2.0-1011.11USN-6466-1

linux-image-6.2.0-1011-nvidia-64kUbuntu

Fixed in:6.2.0-1011.11USN-6466-1

linux-image-6.2.0-1015-awsUbuntu

Fixed in:6.2.0-1015.15~22.04.1USN-6464-1

Fixed in:6.2.0-1015.15USN-6464-1

linux-image-6.2.0-1015-oracleUbuntu

Fixed in:6.2.0-1015.15USN-6464-1

linux-image-6.2.0-1016-azureUbuntu

Fixed in:6.2.0-1016.16~22.04.1USN-6464-1

Fixed in:6.2.0-1016.16USN-6464-1

linux-image-6.2.0-1016-azure-fdeUbuntu

Fixed in:6.2.0-1016.16~22.04.1.1USN-6464-1

linux-image-6.2.0-1016-kvmUbuntu

Fixed in:6.2.0-1016.16USN-6464-1

linux-image-6.2.0-1016-lowlatencyUbuntu

Fixed in:6.2.0-1016.16~22.04.1USN-6464-1

Fixed in:6.2.0-1016.16USN-6464-1

linux-image-6.2.0-1016-lowlatency-64kUbuntu

Fixed in:6.2.0-1016.16~22.04.1USN-6464-1

Fixed in:6.2.0-1016.16USN-6464-1

linux-image-6.2.0-1016-raspiUbuntu

Fixed in:6.2.0-1016.18USN-6464-1

linux-image-6.2.0-1018-gcpUbuntu

Fixed in:6.2.0-1018.20~22.04.1USN-6464-1

Fixed in:6.2.0-1018.20USN-6464-1

linux-image-6.2.0-36-genericUbuntu

Fixed in:6.2.0-36.37~22.04.1USN-6464-1

Fixed in:6.2.0-36.37USN-6464-1

linux-image-6.2.0-36-generic-64kUbuntu

Fixed in:6.2.0-36.37~22.04.1USN-6464-1

Fixed in:6.2.0-36.37USN-6464-1

linux-image-6.2.0-36-generic-lpaeUbuntu

Fixed in:6.2.0-36.37~22.04.1USN-6464-1

Fixed in:6.2.0-36.37USN-6464-1

linux-image-awsUbuntu

Fixed in:5.15.0.1047.52~20.04.35USN-6416-1

Fixed in:6.2.0.1015.15~22.04.1USN-6464-1

Fixed in:6.2.0.1015.16USN-6464-1

linux-image-aws-lts-22.04Ubuntu

Fixed in:5.15.0.1047.46USN-6416-1

linux-image-azureUbuntu

Fixed in:5.15.0.1049.56~20.04.38USN-6416-1

Fixed in:6.2.0.1016.16~22.04.1USN-6464-1

Fixed in:6.2.0.1016.16USN-6464-1

linux-image-azure-cvmUbuntu

Fixed in:5.15.0.1049.56~20.04.38USN-6416-1

linux-image-azure-fdeUbuntu

Fixed in:5.15.0.1049.56~20.04.1.27USN-6416-1

Fixed in:6.2.0.1016.16~22.04.1.13USN-6464-1

linux-image-azure-fde-lts-22.04Ubuntu

Fixed in:5.15.0.1049.56.27USN-6416-1

linux-image-azure-lts-22.04Ubuntu

Fixed in:5.15.0.1049.45USN-6416-1

linux-image-gcpUbuntu

Fixed in:5.15.0.1044.52~20.04.1USN-6416-1

Fixed in:6.2.0.1018.20~22.04.1USN-6464-1

Fixed in:6.2.0.1018.18USN-6464-1

linux-image-gcp-lts-22.04Ubuntu

Fixed in:5.15.0.1044.40USN-6416-1

linux-image-genericUbuntu

Fixed in:5.15.0.86.83USN-6416-1

Fixed in:6.2.0.36.36USN-6464-1

linux-image-generic-64kUbuntu

Fixed in:5.15.0.86.83USN-6416-1

Fixed in:6.2.0.36.36USN-6464-1

linux-image-generic-64k-hwe-20.04Ubuntu

Fixed in:5.15.0.86.96~20.04.44USN-6416-2

linux-image-generic-64k-hwe-22.04Ubuntu

Fixed in:6.2.0.36.37~22.04.14USN-6464-1

linux-image-generic-hwe-20.04Ubuntu

Fixed in:5.15.0.86.96~20.04.44USN-6416-2

linux-image-generic-hwe-22.04Ubuntu

Fixed in:6.2.0.36.37~22.04.14USN-6464-1

linux-image-generic-lpaeUbuntu

Fixed in:5.15.0.86.83USN-6416-1

Fixed in:6.2.0.36.36USN-6464-1

linux-image-generic-lpae-hwe-20.04Ubuntu

Fixed in:5.15.0.86.96~20.04.44USN-6416-2

linux-image-generic-lpae-hwe-22.04Ubuntu

Fixed in:6.2.0.36.37~22.04.14USN-6464-1

linux-image-gkeUbuntu

Fixed in:5.15.0.1044.43USN-6416-1

linux-image-gke-5.15Ubuntu

Fixed in:5.15.0.1044.43USN-6416-1

linux-image-gkeopUbuntu

Fixed in:5.15.0.1030.29USN-6416-1

linux-image-gkeop-5.15Ubuntu

Fixed in:5.15.0.1030.35~20.04.26USN-6416-1

Fixed in:5.15.0.1030.29USN-6416-1

linux-image-ibmUbuntu

Fixed in:5.15.0.1040.43~20.04.12USN-6416-1

Fixed in:5.15.0.1040.36USN-6416-1

linux-image-intelUbuntu

Fixed in:5.15.0.1043.49~20.04.33USN-6445-2

linux-image-intel-iotgUbuntu

Fixed in:5.15.0.1043.49~20.04.33USN-6445-2

Fixed in:5.15.0.1043.43USN-6445-1

linux-image-kvmUbuntu

Fixed in:5.15.0.1044.40USN-6416-1

Fixed in:6.2.0.1016.16USN-6464-1

linux-image-lowlatencyUbuntu

Fixed in:5.15.0.86.88USN-6416-1

Fixed in:6.2.0.1016.16USN-6464-1

linux-image-lowlatency-64kUbuntu

Fixed in:5.15.0.86.88USN-6416-1

Fixed in:6.2.0.1016.16USN-6464-1

linux-image-lowlatency-64k-hwe-20.04Ubuntu

Fixed in:5.15.0.86.95~20.04.41USN-6416-1

linux-image-lowlatency-64k-hwe-22.04Ubuntu

Fixed in:6.2.0.1016.16~22.04.13USN-6464-1

linux-image-lowlatency-hwe-20.04Ubuntu

Fixed in:5.15.0.86.95~20.04.41USN-6416-1

linux-image-lowlatency-hwe-22.04Ubuntu

Fixed in:6.2.0.1016.16~22.04.13USN-6464-1

linux-image-nvidiaUbuntu

Fixed in:5.15.0.1037.37USN-6416-1

linux-image-nvidia-6.2Ubuntu

Fixed in:6.2.0.1011.13USN-6466-1

linux-image-nvidia-64k-6.2Ubuntu

Fixed in:6.2.0.1011.13USN-6466-1

linux-image-nvidia-64k-hwe-22.04Ubuntu

Fixed in:6.2.0.1011.13USN-6466-1

linux-image-nvidia-hwe-22.04Ubuntu

Fixed in:6.2.0.1011.13USN-6466-1

linux-image-nvidia-lowlatencyUbuntu

Fixed in:5.15.0.1037.37USN-6416-1

linux-image-oem-20.04Ubuntu

Fixed in:5.15.0.86.96~20.04.44USN-6416-2

linux-image-oem-20.04bUbuntu

Fixed in:5.15.0.86.96~20.04.44USN-6416-2

linux-image-oem-20.04cUbuntu

Fixed in:5.15.0.86.96~20.04.44USN-6416-2

linux-image-oem-20.04dUbuntu

Fixed in:5.15.0.86.96~20.04.44USN-6416-2

linux-image-oracleUbuntu

Fixed in:5.15.0.1045.51~20.04.1USN-6416-2

Fixed in:5.15.0.1045.40USN-6416-1

Fixed in:6.2.0.1015.15USN-6464-1

linux-image-oracle-lts-22.04Ubuntu

Fixed in:5.15.0.1045.40USN-6416-1

linux-image-raspiUbuntu

Fixed in:5.15.0.1040.38USN-6416-3

Fixed in:6.2.0.1016.19USN-6464-1

linux-image-raspi-nolpaeUbuntu

Fixed in:5.15.0.1040.38USN-6416-3

Fixed in:6.2.0.1016.19USN-6464-1

linux-image-starfiveUbuntu

Fixed in:6.2.0.1009.10~22.04.2USN-6520-1

Fixed in:6.2.0.1008.11USN-6464-1

linux-image-virtualUbuntu

Fixed in:5.15.0.86.83USN-6416-1

Fixed in:6.2.0.36.36USN-6464-1

linux-image-virtual-hwe-20.04Ubuntu

Fixed in:5.15.0.86.96~20.04.44USN-6416-2

linux-image-virtual-hwe-22.04Ubuntu

Fixed in:6.2.0.36.37~22.04.14USN-6464-1

linux-intel-iotgUbuntu

Fixed in:5.15.0-1043.49USN-6445-1

linux-intel-iotg-5.15Ubuntu

Fixed in:5.15.0-1043.49~20.04.1USN-6445-2

linux-kvmUbuntu

Fixed in:5.15.0-1044.49USN-6416-1

Fixed in:6.2.0-1016.16USN-6464-1

linux-lowlatencyUbuntu

Fixed in:5.15.0-86.95USN-6416-1

Fixed in:6.2.0-1016.16USN-6464-1

linux-lowlatency-hwe-5.15Ubuntu

Fixed in:5.15.0-86.95~20.04.1USN-6416-1

linux-lowlatency-hwe-6.2Ubuntu

Fixed in:6.2.0-1016.16~22.04.1USN-6464-1

linux-nvidiaUbuntu

Fixed in:5.15.0-1037.37USN-6416-1

linux-nvidia-6.2Ubuntu

Fixed in:6.2.0-1011.11USN-6466-1

linux-oracleUbuntu

Fixed in:5.15.0-1045.51USN-6416-1

Fixed in:6.2.0-1015.15USN-6464-1

linux-oracle-5.15Ubuntu

Fixed in:5.15.0-1045.51~20.04.1USN-6416-2

linux-raspiUbuntu

Fixed in:5.15.0-1040.43USN-6416-3

Fixed in:6.2.0-1016.18USN-6464-1

linux-starfiveUbuntu

Fixed in:6.2.0-1008.9USN-6464-1

linux-starfive-6.2Ubuntu

Fixed in:6.2.0-1009.10~22.04.1USN-6520-1

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploit Intelligence

9.64%probability of exploitation in 30 days

95thpercentile

Very high risk: more likely to be exploited than 95% of all known CVEs.

References

Patch4

Related Vulnerabilities

Other CWE-476 (NULL Pointer Dereference) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2023-21758	High	7.5	93%	-	Fix
CVE-2023-21547	High	7.5	89%	-	Fix
CVE-2014-3470	Medium	4.3	86%	-	Fix
CVE-2021-44224	High	8.2	82%	-	Fix
CVE-2016-0742	High	7.5	82%	-	Fix
CVE-2009-1386	Medium	5.0	80%	-	Fix

Common questions

How do I fix CVE-2023-3866?

Published advisories record a fix for 118 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2023-3866 being actively exploited?

Not that we know of. CVE-2023-3866 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 9.6% is the estimated probability that it will be exploited in the next 30 days. That is higher than 95% of all scored CVEs.

How severe is CVE-2023-3866?

CVE-2023-3866 has a CVSS v3 base score of 7.5, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2023-3866 affect?

Published advisories record a fix for linux (Debian), linux (Ubuntu), linux-aws (Ubuntu), linux-aws-5.15 (Ubuntu), and 114 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2023-3866

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-08-04.