VDB-363436 · CVE-2026-8449 · GCVE-0-2026-8449

Linux ksmbd DACL out-of-bounds

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
8.6	$0-$5k	0.00

Summaryinfo

A vulnerability labeled as problematic has been found in Linux ksmbd. The impacted element is an unknown function of the component DACL Handler. Executing a manipulation can lead to out-of-bounds. This vulnerability is handled as CVE-2026-8449. The attack can be executed remotely. There is not any exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Linux ksmbd (the affected version unknown). It has been declared as critical. This vulnerability affects an unknown part of the component DACL Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Linux ksmbd contains a remote memory corruption vulnerability in the ACL inheritance path that allows remote clients with directory creation permissions to trigger a heap out-of-bounds read and subsequent heap corruption by setting a crafted DACL with a malformed SID containing an inflated num_subauth field. Attackers can exploit this vulnerability by creating a directory, setting the malicious DACL via SMB2_SET_INFO, and creating child entries to cause kernel instability, denial of service, or potentially achieve privilege escalation to kernel code execution.

The weakness was released by Shota Zaizen. The advisory is shared for download at github.com. This vulnerability was named CVE-2026-8449 since 05/12/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 05/13/2026).

Applying the patch 996454b is able to eliminate this problem. The bugfix is ready for download at github.com.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Linux

Name

ksmbd

License

open-source

Website

Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.6

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 996454b

Timelineinfo

05/12/2026 CVE reserved
05/13/2026 +1 days Advisory disclosed
05/13/2026 +0 days VulDB entry created
05/13/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: github.com
Researcher: Shota Zaizen
Status: Confirmed

CVE: CVE-2026-8449 (🔒)
GCVE (CVE): GCVE-0-2026-8449
GCVE (VulDB): GCVE-100-363436

Entryinfo

Created: 05/13/2026 06:47
Changes: 05/13/2026 06:47 (77)
Complete: 🔍
Cache ID: 216::103