High severity · published Apr 17, 2025
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
8.8
CVSS
0.2%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 14% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
2.6.31 before 4.4.254; 4.5 before 4.9.254; 4.10 before 4.14.218; 4.15 before 4.19.171; 4.20 before 5.4.93; 5.5 before 5.10.11; +4 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-47668
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-47668
Patch
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
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