CVE-2021-28691

Guest triggered use-after-free in Linux xen-netback A malicious or buggy network PV frontend can force Linux netback to disable the interface and terminate the receive kernel thread associated with queue 0 in response to the frontend sending a malformed packet. Such kernel thread termination will lead to a use-after-free in Linux netback when the backend is destroyed, as the kernel thread associated with queue 0 will have already exited and thus the call to kthread_stop will be performed against a stale pointer.

CVSS v3.0 7.8 HIGH
CVSS v2.0 4.6 MEDIUM

7.8^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

4.6^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 3.9 / Impact : 6.4

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://xenbits.xenproject.org/xsa/advisory-374.txt	Third Party Advisory
https://security.gentoo.org/glsa/202107-30

Configurations

Configuration 1 (hide)

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

Information

Published : 2021-06-29 12:15

Updated : 2021-08-05 12:15

NVD link : CVE-2021-28691

Mitre link : CVE-2021-28691

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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