CVE-2021-47293
net/sched: act_skbmod: Skip non-Ethernet packets
- Published
- Updated
- Reserved
- Assigned by
- Linux
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Analyzed | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.23% · top 86% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected 86da71b57383d40993cb90baafb3735cffe5d800 – < e4fdca366806f6bab374d1a95e626a10a3854b0c
- affected 86da71b57383d40993cb90baafb3735cffe5d800 – < a88414fb1117f2fe65fb88e45ba694e1d09d5024
- affected 86da71b57383d40993cb90baafb3735cffe5d800 – < 071729150be9e1d1b851b70efb6d91ee9269d57b
- affected 86da71b57383d40993cb90baafb3735cffe5d800 – < 34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d
- affected 86da71b57383d40993cb90baafb3735cffe5d800 – < 727d6a8b7ef3d25080fad228b2c4a1d4da5999c6
- affected 4.9
- unaffected < 4.9
- unaffected 4.19.199 – ≤ 4.19.*
- unaffected 5.4.136 – ≤ 5.4.*
- unaffected 5.10.54 – ≤ 5.10.*
- unaffected 5.13.6 – ≤ 5.13.*
- unaffected 5.14 – ≤ *
References (5)
- https://git.kernel.org/stable/c/e4fdca366806f6bab374d1a95e626a10a3854b0c (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/a88414fb1117f2fe65fb88e45ba694e1d09d5024 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/071729150be9e1d1b851b70efb6d91ee9269d57b (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/34f1e1f657fae2891b485a3b2b95fe4d2aef9f0d (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/727d6a8b7ef3d25080fad228b2c4a1d4da5999c6 (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-47293)Record last updated .