CVE-2021-47670 | can: peak_usb: fix use after free bugs

In the Linux kernel, the following vulnerability has been resolved: can: peak_usb: fix use after free bugs After calling peak_usb_netif_rx_ni(skb), dereferencing skb is unsafe. Especially, the can_frame cf which aliases skb memory is accessed after the peak_usb_netif_rx_ni(). Reordering the lines solves the issue.

Published: 2025-04-17 Last update: 2025-04-21 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-47670 is rated Low Risk (36.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.05%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-47670

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-26 0.07% 0.05% -0.02%
2 2026-02-11 0.01% 0.07% +0.06%
3 2025-04-18 — 0.01% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-47670

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2021-47670

OS Trackers for CVE-2021-47670

vendor priority summary link
debian not yet assigned CVE-2021-47670 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-47670
redhat medium — https://access.redhat.com/security/cve/CVE-2021-47670
suse medium — https://www.suse.com/security/cve/CVE-2021-47670/
ubuntu medium CVE-2021-47670 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, ignored 148, not-affected 130, released 124, needed 4. https://ubuntu.com/security/CVE-2021-47670

Affected software / configurations for CVE-2021-47670

Vendor Product Version Raw CPE
linux linux_kernel >= 4.0, < 4.19.171 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.20, < 5.4.93 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.5, < 5.10.11 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 5.11 cpe:2.3:o:linux:linux_kernel:5.11:rc1:*:*:*:*:*:*
linux linux_kernel 5.11 cpe:2.3:o:linux:linux_kernel:5.11:rc2:*:*:*:*:*:*
linux linux_kernel 5.11 cpe:2.3:o:linux:linux_kernel:5.11:rc3:*:*:*:*:*:*
linux linux_kernel 5.11 cpe:2.3:o:linux:linux_kernel:5.11:rc4:*:*:*:*:*:*

References for CVE-2021-47670

cvelogic Threat Intelligence