CVE-2021-47604

In the Linux kernel, the following vulnerability has been resolved: vduse: check that offset is within bounds in get_config() This condition checks "len" but it does not check "offset" and that could result in an out of bounds read if "offset > dev->config_size". The problem is that since both variables are unsigned the "dev->config_size - offset" subtraction would result in a very high unsigned value. I think these checks might not be necessary because "len" and "offset" are supposed to already have been validated using the vhost_vdpa_config_validate() function. But I do not know the code perfectly, and I like to be safe.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/dc1db0060c02d119fd4196924eff2d1129e9a442	Patch
https://git.kernel.org/stable/c/ebbbc5fea3f648175df1aa3f127c78eb0252cc2a	Patch
https://git.kernel.org/stable/c/dc1db0060c02d119fd4196924eff2d1129e9a442	Patch
https://git.kernel.org/stable/c/ebbbc5fea3f648175df1aa3f127c78eb0252cc2a	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2024-06-19 15:15

Updated : 2024-11-21 06:36

NVD link : CVE-2021-47604

Mitre link : CVE-2021-47604

CVE.ORG link : CVE-2021-47604

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-125

Out-of-bounds Read

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