CVE-2021-47293
Last modified
CVE-2021-47293 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: net/sched: act_skbmod: Skip non-Ethernet packets Currently tcf_skbmod_act() assumes that packets use Ethernet as their L2 protocol, which is not always the case. As an example, for CAN devices: $ ip link add dev vcan0 type vcan $ ip link set up vcan0 $ tc qdisc add dev vcan0 root handle 1: htb $ tc filter add dev vcan0 parent 1: protocol ip prio 10 \ matchall action skbmod swap mac Doing the above silently corrupts all the packets. EPSS estimates a 0.23% chance of exploitation in the next 30 days.
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_skbmod: Skip non-Ethernet packets Currently tcf_skbmod_act() assumes that packets use Ethernet as their L2 protocol, which is not always the case. As an example, for CAN devices: $ ip link add dev vcan0 type vcan $ ip link set up vcan0 $ tc qdisc add dev vcan0 root handle 1: htb $ tc filter add dev vcan0 parent 1: protocol ip prio 10 \ matchall action skbmod swap mac Doing the above silently corrupts all the packets. Do not perform skbmod actions for non-Ethernet packets.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Linux | Linux Kernel | >= 4.9, < 4.19.199 | — |
| Linux | Linux Kernel | >= 4.20, < 5.4.136 | — |
| Linux | Linux Kernel | >= 5.5, < 5.10.54 | — |
| Linux | Linux Kernel | >= 5.11, < 5.13.6 | — |
| Linux | Linux Kernel | 5.14 | Rc1 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2021-47293?
How severe is CVE-2021-47293?
How do I fix CVE-2021-47293?
Are you affected by CVE-2021-47293?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST