Use After Free in Linux
CVE-2021-47224
In the Linux kernel, the following vulnerability has been resolved: net: ll_temac: Make sure to free skb when it is completely used With the skb pointer piggy-backed on the TX BD, we have a simple and efficient way to free the skb buffer when the frame has been transmitted. But in order to avoid freeing the skb while there are still fragments from the skb in use, we need to piggy-back on the TX BD of the skb, not the first. Without this, we are doing use-after-free on the DMA side, when the first BD of a multi TX BD packet is seen as completed in xmit_done, and the remaining BDs are still being processed.
Vulnerability class: Use-After-Free
EPSS: 0.002 (14.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions 92744989533cbe85e8057935d230e128810168ce, 2.6.31, 0
- Linux Linux_kernel — versions 5.13
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2021-47224?
- CVE-2021-47224 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 7.8/10. Published 2024-05-21.
- How severe is CVE-2021-47224?
- High severity. CVSS v3 base score is 7.8 out of 10.