Linux Kernel up to 7.0-rc1 ksmbd memcmp timing discrepancy

CVSS Meta Temp Score
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CTI Interest Score
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2.5$0-$5k0.63

Summaryinfo

A vulnerability marked as problematic has been reported in Linux Kernel up to 7.0-rc1. This affects the function memcmp of the component ksmbd. Performing a manipulation results in timing discrepancy. This vulnerability is identified as CVE-2026-23364. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 7.0-rc1. This affects the function memcmp of the component ksmbd. The manipulation with an unknown input leads to a timing discrepancy vulnerability. CWE is classifying the issue as CWE-208. Two separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not. This is going to have an impact on confidentiality. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: ksmbd: Compare MACs in constant time To prevent timing attacks, MAC comparisons need to be constant-time. Replace the memcmp() with the correct function, crypto_memneq().

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-23364 since 01/13/2026. The exploitability is told to be difficult. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

Upgrading to version 6.1.167, 6.6.130, 6.12.78, 6.18.19, 6.19.7 or 7.0-rc2 eliminates this vulnerability. Applying the patch cd52a0e309659537048a864211abc3ea4c5caa63/307afccb751f542246bd5dc68a2c1ffe1a78418c/2cdc56ed67615ba0921383a688f24415ebe065f3/93c0a22fec914ec4b697e464895a0f594e29fb28/f4588b85efd6007d46b80aa1b9fb746628ffb3dc/c5794709bc9105935dbedef8b9cf9c06f2b559fa is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 2.6
VulDB Meta Temp Score: 2.5

VulDB Base Score: 2.6
VulDB Temp Score: 2.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Timing discrepancy
CWE: CWE-208 / CWE-203 / CWE-200
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.167/6.6.130/6.12.78/6.18.19/6.19.7/7.0-rc2
Patch: cd52a0e309659537048a864211abc3ea4c5caa63/307afccb751f542246bd5dc68a2c1ffe1a78418c/2cdc56ed67615ba0921383a688f24415ebe065f3/93c0a22fec914ec4b697e464895a0f594e29fb28/f4588b85efd6007d46b80aa1b9fb746628ffb3dc/c5794709bc9105935dbedef8b9cf9c06f2b559fa

Timelineinfo

01/13/2026 CVE reserved
03/25/2026 +71 days Advisory disclosed
03/25/2026 +0 days VulDB entry created
03/30/2026 +5 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-23364 (🔒)
GCVE (CVE): GCVE-0-2026-23364
GCVE (VulDB): GCVE-100-353091

Entryinfo

Created: 03/25/2026 13:29
Updated: 03/30/2026 11:43
Changes: 03/25/2026 13:29 (59), 03/30/2026 11:43 (1)
Complete: 🔍
Cache ID: 216:EBD:103

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