Vulnerability Details : CVE-2021-47223
In the Linux kernel, the following vulnerability has been resolved:
net: bridge: fix vlan tunnel dst null pointer dereference
This patch fixes a tunnel_dst null pointer dereference due to lockless
access in the tunnel egress path. When deleting a vlan tunnel the
tunnel_dst pointer is set to NULL without waiting a grace period (i.e.
while it's still usable) and packets egressing are dereferencing it
without checking. Use READ/WRITE_ONCE to annotate the lockless use of
tunnel_id, use RCU for accessing tunnel_dst and make sure it is read
only once and checked in the egress path. The dst is already properly RCU
protected so we don't need to do anything fancy than to make sure
tunnel_id and tunnel_dst are read only once and checked in the egress path.
Vulnerability category: Memory Corruption
Products affected by CVE-2021-47223
- 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:5.13:rc1:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:*
Exploit prediction scoring system (EPSS) score for CVE-2021-47223
0.04%
Probability of exploitation activity in the next 30 days
EPSS Score History
~ 5 %
Percentile, the proportion of vulnerabilities that are scored at or less
CVSS scores for CVE-2021-47223
Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Score Source | First Seen |
---|---|---|---|---|---|---|
5.5
|
MEDIUM | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
1.8
|
3.6
|
NIST | 2025-02-03 |
CWE ids for CVE-2021-47223
-
The product dereferences a pointer that it expects to be valid but is NULL.Assigned by: nvd@nist.gov (Primary)
References for CVE-2021-47223
-
https://git.kernel.org/stable/c/abb02e05cb1c0a30dd873a29f33bc092067dc35d
net: bridge: fix vlan tunnel dst null pointer dereference - kernel/git/stable/linux.git - Linux kernel stable treePatch
-
https://git.kernel.org/stable/c/ad7feefe7164892db424c45687472db803d87f79
net: bridge: fix vlan tunnel dst null pointer dereference - kernel/git/stable/linux.git - Linux kernel stable treePatch
-
https://git.kernel.org/stable/c/24a6e55f17aa123bc1fc54b7d3c410b41bc16530
net: bridge: fix vlan tunnel dst null pointer dereference - kernel/git/stable/linux.git - Linux kernel stable treePatch
-
https://git.kernel.org/stable/c/58e2071742e38f29f051b709a5cca014ba51166f
net: bridge: fix vlan tunnel dst null pointer dereference - kernel/git/stable/linux.git - Linux kernel stable treePatch
-
https://git.kernel.org/stable/c/fe0448a3fad365a747283a00a1d1ad5e8d6675b7
net: bridge: fix vlan tunnel dst null pointer dereference - kernel/git/stable/linux.git - Linux kernel stable treePatch
-
https://git.kernel.org/stable/c/a2241e62f6b4a774d8a92048fdf59c45f6c2fe5c
net: bridge: fix vlan tunnel dst null pointer dereference - kernel/git/stable/linux.git - Linux kernel stable treePatch
Jump to