CVE-2021-47668

In the Linux kernel, the following vulnerability has been resolved: can: dev: can_restart: fix use after free bug After calling netif_rx_ni(skb), dereferencing skb is unsafe. Especially, the can_frame cf which aliases skb memory is accessed after the netif_rx_ni() in: stats->rx_bytes += cf->len; Reordering the lines solves the issue.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : 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

References

Link	Resource
https://git.kernel.org/stable/c/03f16c5075b22c8902d2af739969e878b0879c94	Patch
https://git.kernel.org/stable/c/08ab951787098ae0b6c0364aeea7a8138226f234	Patch
https://git.kernel.org/stable/c/260925a0b7d2da5449f8ecfd02c1405e0c8a45b8	Patch
https://git.kernel.org/stable/c/593c072b7b3c4d7044416eb039d9ad706bedd67a	Patch
https://git.kernel.org/stable/c/92668d28c7e6a7a2ba07df287669ffcdf650c421	Patch
https://git.kernel.org/stable/c/ac48ef15826e83f4206c47add61072e8fc76d328	Patch
https://git.kernel.org/stable/c/bbc6847b9b8978b520f62fbc7c68c54ef0f8d282	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::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:5.11:rc1::::::
	cpe:2.3:o:linux:linux_kernel:5.11:rc2::::::
	cpe:2.3:o:linux:linux_kernel:5.11:rc3::::::
	cpe:2.3:o:linux:linux_kernel:5.11:rc4::::::

History

No history.

Information

Published : 2025-04-17 18:15

Updated : 2025-04-21 18:41

NVD link : CVE-2021-47668

Mitre link : CVE-2021-47668

CVE.ORG link : CVE-2021-47668

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-416

Use After Free

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