cpufreq: intel_pstate: Fix NULL pointer dereference in update_cpu_qos_request()
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-476.
Summary
In the Linux kernel, the following vulnerability has been resolved: cpufreq: intel_pstate: Fix NULL pointer dereference in update_cpu_qos_request() The update_cpu_qos_request() function attempts to initialize the 'freq' variable by dereferencing 'cpudata' before verifying if the 'policy' is valid. This issue occurs on systems booted with the "nosmt" parameter, where all_cpu_data[cpu] is NULL for the SMT sibling threads. As a result, any call to update_qos_requests() will result in a NULL pointer dereference as the code will attempt to access pstate.turbo_freq using the NULL cpudata pointer. Also, pstate.turbo_freq may be updated by intel_pstate_get_hwp_cap() after initializing the 'freq' variable, so it is better to defer the 'freq' until intel_pstate_get_hwp_cap() has been called. Fix this by deferring the 'freq' assignment until after the policy and driver_data have been validated. [ rjw: Added one paragraph to the changelog ]
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 | 6.18 and later | 6.18.19, 6.19.9, 7.0 | Patch available | CNA |
- Linux VendorLinux Affected 6.18 and later Fixed in 6.18.19, 6.19.9, 7.0 Patch available CNA
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.18.19, 6.19.9, 7.0
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 4 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2026-43401
- 2026-10-03 Alias added: GHSA-j7hx-vp8g-c83p
- 2026-10-29 Affected versions changed · Red Hat
- 2026-11-06 CISA SSVC decision points changed
References
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-2026-43401 · CVE Program
- CVE-2026-43401 · NVD
- FIRST EPSS
- GHSA-j7hx-vp8g-c83p · GitHub Advisory Database · CC BY 4.0
- CVE-2026-43401 · Red Hat security data · CC BY 4.0
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