can: dev: can_restart: fix use after free bug
Priority MEDIUM 40CWE-416Published · Updated
Key facts
- Attack vector
- Adjacent network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00235 14th percentileScored 2026-11-07
Fix Partial Linux (Linux): 4.4.254, 4.9.254, 4.14.218 +4Red Hat: 3 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 2.6.31 and later | 4.4.254, 4.9.254, 4.14.218, 4.19.171, 5.4.93, 5.10.11, 5.11 | Patch available | CNA |
- Linux VendorLinux Affected 2.6.31 and later Fixed in 4.4.254, 4.9.254, 4.14.218, 4.19.171, 5.4.93, 5.10.11, 5.11 Patch available CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 2.6.31 to before 4.4.254; 4.5 to before 4.9.254; 4.10 to before 4.14.218; 4.15 to before 4.19.171; 4.20 to before 5.4.93; 5.5 to before 5.10.11 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.11:rc1:*:*:*:*:*:* | 5.11 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.11:rc2:*:*:*:*:*:* | 5.11 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.11:rc3:*:*:*:*:*:* | 5.11 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:5.11:rc4:*:*:*:*:*:* | 5.11 rc4 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.31 to before 4.4.254; 4.5 to before 4.9.254; 4.10 to before 4.14.218; 4.15 to before 4.19.171; 4.20 to before 5.4.93; 5.5 to before 5.10.11 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.11:rc1:*:*:*:*:*:* Versions 5.11 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.11:rc2:*:*:*:*:*:* Versions 5.11 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.11:rc3:*:*:*:*:*:* Versions 5.11 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:5.11:rc4:*:*:*:*:*:* Versions 5.11 rc4 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 4.4.254, 4.9.254, 4.14.218, 4.19.171, 5.4.93, 5.10.11, 5.11
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Out of support scope |
Not affected: 2 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2021-47668
- 2026-10-03 Alias added: GHSA-78xp-xvw2-6rw6
References
Patch 7
- https://git.kernel.org/stable/c/260925a0b7d2da5449f8ecfd02c1405e0c8a45b8
- https://git.kernel.org/stable/c/bbc6847b9b8978b520f62fbc7c68c54ef0f8d282
- https://git.kernel.org/stable/c/92668d28c7e6a7a2ba07df287669ffcdf650c421
- https://git.kernel.org/stable/c/08ab951787098ae0b6c0364aeea7a8138226f234
- https://git.kernel.org/stable/c/ac48ef15826e83f4206c47add61072e8fc76d328
- https://git.kernel.org/stable/c/593c072b7b3c4d7044416eb039d9ad706bedd67a
- https://git.kernel.org/stable/c/03f16c5075b22c8902d2af739969e878b0879c94
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2021-47668 · CVE Program
- CVE-2021-47668 · NVD
- FIRST EPSS
- GHSA-78xp-xvw2-6rw6 · GitHub Advisory Database · CC BY 4.0
- CVE-2021-47668 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences