CVE-2021-47293
Linux net/sched: Act_skbmod Ethernet Protocol Vulnerability
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.
INFO
Published Date :
May 21, 2024, 3:15 p.m.
Last Modified :
May 7, 2025, 5:51 p.m.
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Remotely Exploitable :
No
Impact Score :
5.9
Exploitability Score :
1.8
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-47293.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2021-47293 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-47293 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
May. 07, 2025
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Added CWE NVD-CWE-noinfo Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:5.14:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:5.14:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.20 up to (excluding) 5.4.136 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.5 up to (excluding) 5.10.54 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.13.6 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 4.9 up to (excluding) 4.19.199 Added Reference Type CVE: https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57b Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57b Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6 Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024 Types: Patch Added Reference Type CVE: https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0c Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0c Types: Patch -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57b Added Reference https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d Added Reference https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6 Added Reference https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024 Added Reference https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0c -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 28, 2024
Action Type Old Value New Value -
CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 21, 2024
Action Type Old Value New Value Added 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. Added Reference kernel.org https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0c [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57b [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6 [No types assigned]
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-47293 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-47293
weaknesses.