CVE-2021-47668

can: dev: can_restart: fix use after free bug

HIGH
8.8
CVSS Score
Published: April 17, 2025 at 06:01 PM UTC
Updated: August 5, 2026 at 09:24 AM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH8.8
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

In the Linux kernel, the following vulnerability has been resolved: can: dev: can_restart: fix use after free bug After calling netif_rx_ni(skb), dereferencing skb is unsafe. Especially, the can_frame cf which aliases skb memory is accessed after the netif_rx_ni() in: stats->rx_bytes += cf->len; Reordering the lines solves the issue.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

2.6.31 ≤ v < 4.14.2182.6.31 ≤ v < 4.19.1712.6.31 ≤ v < 4.4.2542.6.31 ≤ v < 4.9.2542.6.31 ≤ v < 5.10.112.6.31 ≤ v < 5.112.6.31 ≤ v < 5.4.934.10 ≤ v < 4.14.2184.15 ≤ v < 4.19.1714.20 ≤ v < 5.4.934.5 ≤ v < 4.9.2545.5 ≤ v < 5.10.1139549eef3587f1c1e8c65c88a2400d10fd30ea175.11 rc15.11 rc25.11 rc35.11 rc4
Vendor states this is fixed in 03f16c5075b22c8902d2af739969e878b0879c94 (fixed)
Vendor states this is fixed in 08ab951787098ae0b6c0364aeea7a8138226f234 (fixed)
Vendor states this is fixed in 260925a0b7d2da5449f8ecfd02c1405e0c8a45b8 (fixed)
Vendor states this is fixed in 593c072b7b3c4d7044416eb039d9ad706bedd67a (fixed)
Vendor states this is fixed in 92668d28c7e6a7a2ba07df287669ffcdf650c421 (fixed)
Vendor states this is fixed in ac48ef15826e83f4206c47add61072e8fc76d328 (fixed)
Vendor states this is fixed in bbc6847b9b8978b520f62fbc7c68c54ef0f8d282 (fixed)
Vendor states this is fixed in 2.6.31 (unaffected)
Vendor states this is fixed in 4.14.218 (unaffected)
Vendor states this is fixed in 4.19.171 (unaffected)
Vendor states this is fixed in 4.4.254 (unaffected)
Vendor states this is fixed in 4.9.254 (unaffected)
Vendor states this is fixed in 5.10.11 (unaffected)
Vendor states this is fixed in 5.11 (unaffected)
Vendor states this is fixed in 5.4.93 (unaffected)

References (7)

Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/03f16c5075b22c8902d2af739969e878b0879c94
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/08ab951787098ae0b6c0364aeea7a8138226f234
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/260925a0b7d2da5449f8ecfd02c1405e0c8a45b8
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/593c072b7b3c4d7044416eb039d9ad706bedd67a
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/92668d28c7e6a7a2ba07df287669ffcdf650c421
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/ac48ef15826e83f4206c47add61072e8fc76d328
Patch
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/bbc6847b9b8978b520f62fbc7c68c54ef0f8d282

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.8HIGHLinux
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-416

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