What’s Vulnerable › Vulnerabilities

CVE-2021-47670: can: peak_usb: fix use after free bugs

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-04-17 · updated 2026-08-04
• Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: can: peak_usb: fix use after free bugs After calling peak_usb_netif_rx_ni(skb), dereferencing skb is unsafe. Especially, the can_frame cf which aliases skb memory is accessed after the peak_usb_netif_rx_ni(). Reordering the lines solves the issue.

Affected products

• Linux kernel: from 4.0 before 4.19.171; from 4.20 before 5.4.93; from 5.5 before 5.10.11; 5.11-rc1, 5.11-rc2, 5.11-rc3, 5.11-rc4 — fixed in 4.19.171, 5.10.11, 5.4.93

How to fix

Upgrade to a fixed version: Linux kernel 4.19.171, 5.10.11, 5.4.93. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/50aca891d7a554db0901b245167cd653d73aaa71
• https://git.kernel.org/stable/c/5408824636fa0dfedb9ecb0d94abd573131bfbbe
• https://git.kernel.org/stable/c/ddd1416f44130377798c1430b76503513b7497c2
• https://git.kernel.org/stable/c/ec939c13c3fff2114479769c8380b7f1a54feca9

Get alerted when CVE-2021-47670 or the next vulnerability affects your stack