Linux ksmbd Remote Memory Corruption via ACL Inheritance_CVE-2026-8449

8.8 / 10

HIGH

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

Description

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.

Basic Information

ID CVE-2026-8449

Source VulnCheck

Published May 12, 2026 at 21:34

Modified May 12, 2026 at 21:35

Affected Product

Vendor Linux

Product ksmbd

Affected Versions Linux ksmbd 0

CWE Classification

CWE-125

References

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    "published": "2026-05-12T21:34:59.782Z",
    "modified": "2026-05-12T21:35:59.938Z",
    "type": "cve",
    "title": "Linux ksmbd Remote Memory Corruption via ACL Inheritance",
    "source": "VulnCheck",
    "references": "https://github.com/torvalds/linux/blob/6596a02b207886e9e00bb0161c7fd59fea53c081/fs/smb/server/smbacl.c\nhttps://github.com/torvalds/linux/commit/996454bc0da84d5a1dedb1a7861823087e01a7ae\nhttps://www.vulncheck.com/advisories/linux-ksmbd-remote-memory-corruption-via-acl-inheritance",
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