Use After Free in Linux
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.
Vulnerability class: Use-After-Free
EPSS: 0.002 (7.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions 39549eef3587f1c1e8c65c88a2400d10fd30ea17, 2.6.31, 0
- Linux Linux_kernel — versions 5.11
Weakness classification (CWE)
References
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
Frequently asked questions
- What is CVE-2021-47668?
- CVE-2021-47668 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 8.8/10. Published 2025-04-17.
- How severe is CVE-2021-47668?
- High severity. CVSS v3 base score is 8.8 out of 10.