hwmon: (w83791d) Convert macros to functions to avoid TOCTOU
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 5 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: hwmon: (w83791d) Convert macros to functions to avoid TOCTOU The macro FAN_FROM_REG evaluates its arguments multiple times. When used in lockless contexts involving shared driver data, this leads to Time-of-Check to Time-of-Use (TOCTOU) race conditions, potentially causing divide-by-zero errors. Convert the macro to a static function. This guarantees that arguments are evaluated only once (pass-by-value), preventing the race conditions. Additionally, in store_fan_div, move the calculation of the minimum limit inside the update lock. This ensures that the read-modify-write sequence operates on consistent data. Adhere to the principle of minimal changes by only converting macros that evaluate arguments multiple times and are used in lockless contexts.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
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 | 2.6.18 and later | 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.3, 6.19 | Patch available | CNA |
- Linux VendorLinux Affected 2.6.18 and later Fixed in 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.3, 6.19 Patch available CNA
CPE configurations NVD · 10
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 2.6.18.1 to before 5.10.248; 5.11 to before 5.15.198; 5.16 to before 6.1.160; 6.2 to before 6.6.120; 6.7 to before 6.12.64; 6.13 to before 6.18.3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:2.6.18:-:*:*:*:*:*:* | 2.6.18 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:* | 6.19 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:* | 6.19 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:* | 6.19 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:* | 6.19 rc4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:* | 6.19 rc5 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:* | 6.19 rc6 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:* | 6.19 rc7 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:* | 6.19 rc8 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.18.1 to before 5.10.248; 5.11 to before 5.15.198; 5.16 to before 6.1.160; 6.2 to before 6.6.120; 6.7 to before 6.12.64; 6.13 to before 6.18.3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:2.6.18:-:*:*:*:*:*:* Versions 2.6.18 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:* Versions 6.19 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:* Versions 6.19 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:* Versions 6.19 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:* Versions 6.19 rc4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:* Versions 6.19 rc5 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc6:*:*:*:*:*:* Versions 6.19 rc6 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:* Versions 6.19 rc7 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:* Versions 6.19 rc8 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.3, 6.19
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet |
| Red Hat Enterprise Linux 8 | Affected | No fix yet |
| Red Hat Enterprise Linux 9 | Affected | No fix yet |
Timeline
- 2026-10-02 Threatist record created from CVE-2025-71111
- 2026-10-03 Alias added: GHSA-w25h-64gv-grq6
- 2026-10-19 Weakness changed · CISA ADP
References
Patch 7
- https://git.kernel.org/stable/c/3dceb68f6ad33156032ef4da21a93d84059cca6d
- https://git.kernel.org/stable/c/bf5b03227f2e6d4360004886d268f9df8993ef8f
- https://git.kernel.org/stable/c/f2b579a0c37c0df19603d719894a942a295f634a
- https://git.kernel.org/stable/c/f94800fbc26ccf7c81eb791707b038a57aa39a18
- https://git.kernel.org/stable/c/a9fb6e8835a22f5796c1182ed612daed3fd273af
- https://git.kernel.org/stable/c/c8cf0c2bdcccc6634b6915ff793b844e12436680
- https://git.kernel.org/stable/c/670d7ef945d3a84683594429aea6ab2cdfa5ceb4
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- 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-2025-71111 · CVE Program
- CVE-2025-71111 · NVD
- FIRST EPSS
- GHSA-w25h-64gv-grq6 · GitHub Advisory Database · CC BY 4.0
- CVE-2025-71111 · Red Hat security data · CC BY 4.0
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