CVE-2026-43185

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix signededness bug in smb_direct_prepare_negotiation() smb_direct_prepare_negotiation() casts an unsigned __u32 value from sp->max_recv_size and req->preferred_send_size to a signed int before computing min_t(int, ...). A maliciously provided preferred_send_size of 0x80000000 will return as smaller than max_recv_size, and then be used to set the maximum allowed alowed receive size for the next message. By sending a second message with a large value (>1420 bytes) the attacker can then achieve a heap buffer overflow. This fix replaces min_t(int, ...) with min_t(u32)

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/55abc475d096da4a5356b6efb0cfdc6156bc1550	Patch
https://git.kernel.org/stable/c/6b4f875aac344cdd52a1f34cc70ed2f874a65757	Patch
https://git.kernel.org/stable/c/ceae058eb707ddd0d68f0872f9d9f23b7c30c37b	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::

History

No history.

Information

Published : 2026-05-06 12:16

Updated : 2026-06-17 10:49

NVD link : CVE-2026-43185

Mitre link : CVE-2026-43185

CVE.ORG link : CVE-2026-43185

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-674

Uncontrolled Recursion

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