wifi: iwlwifi: mld: stop TX during firmware restart
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-400.
Summary
In the Linux kernel, the following vulnerability has been resolved: wifi: iwlwifi: mld: stop TX during firmware restart When iwlwifi firmware crashes (e.g., NMI_INTERRUPT_UNKNOWN on Intel BE201/Wi-Fi 7), iwl_mld_nic_error() sets mld->fw_status.in_hw_restart to true. However, iwl_mld_tx_from_txq() does not check this flag before dequeuing frames from mac80211 and pushing them to the transport layer. Since the firmware is dead, iwl_trans_tx() returns -EIO for each frame, which then gets freed immediately. Under high-throughput conditions (e.g., Tailscale UDP traffic or active SSH sessions), this creates a tight dequeue-send-fail-free loop that wastes CPU cycles and generates rapid skb allocation churn, leading to memory pressure from slab fragmentation. The RX path already has this guard (iwl_mld_rx_mpdu checks in_hw_restart at rx.c:1906), and so does the TXQ allocation worker (iwl_mld_add_txqs_wk at tx.c:156). Add the same guard to iwl_mld_tx_from_txq() to stop all TX during firmware restart. Frames left in mac80211's TXQs are naturally drained after restart completes, when queue reallocation triggers iwl_mld_tx_from_txq() via iwl_mld_add_txq_list(), or when new upper-layer traffic invokes wake_tx_queue. Tested on ASUS Zenbook 14 UX3405CA with Intel BE201 (Wi-Fi 7) on kernel 6.19.5 where the firmware crashes approximately every 10-15 minutes under Tailscale traffic.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- 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 | 6.15 and later | 6.18.34, 7.0.11, 7.1 | Patch available | CNA |
- Linux VendorLinux Affected 6.15 and later Fixed in 6.18.34, 7.0.11, 7.1 Patch available CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 6.15 to before 6.18.34; 6.19 to before 7.0.11 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* | 7.1 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* | 7.1 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* | 7.1 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* | 7.1 rc4 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.15 to before 6.18.34; 6.19 to before 7.0.11 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* Versions 7.1 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* Versions 7.1 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* Versions 7.1 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* Versions 7.1 rc4 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.18.34, 7.0.11, 7.1
Red Hat 2 advisories
- RHSA-2026:68570 Released 2026-09-17 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.49.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.49.1.el9_8, kernel-64k-devel-5.14.0-687.49.1.el9_8 +12
- Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.49.1.el9_8, kernel-64k-5.14.0-687.49.1.el9_8, kernel-64k-core-5.14.0-687.49.1.el9_8 +28
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.49.1.el9_8, libperf-5.14.0-687.49.1.el9_8
- Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.49.1.el9_8, kernel-rt-64k-5.14.0-687.49.1.el9_8, kernel-rt-64k-core-5.14.0-687.49.1.el9_8 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.49.1.el9_8, kernel-rt-core-5.14.0-687.49.1.el9_8, kernel-rt-debug-5.14.0-687.49.1.el9_8 +9
- RHSA-2026:68507 Released 2026-09-17 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.56.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.56.1.el10_2, kernel-64k-devel-6.12.0-211.56.1.el10_2 +12
- Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.56.1.el10_2, kernel-64k-6.12.0-211.56.1.el10_2, kernel-64k-core-6.12.0-211.56.1.el10_2 +29
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.56.1.el10_2, libperf-6.12.0-211.56.1.el10_2
- Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.56.1.el10_2, kernel-rt-64k-6.12.0-211.56.1.el10_2, kernel-rt-64k-core-6.12.0-211.56.1.el10_2 +21
- Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.56.1.el10_2, kernel-rt-core-6.12.0-211.56.1.el10_2, kernel-rt-debug-6.12.0-211.56.1.el10_2 +9
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:68507 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:68570 |
| Red Hat Enterprise Linux BaseOS (v. 10) | Fixed | RHSA-2026:68507 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2026:68570 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) | Fixed | RHSA-2026:68507 |
| Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) | Fixed | RHSA-2026:68570 |
| Red Hat Enterprise Linux Real Time (v. 10) | Fixed | RHSA-2026:68507 |
| Red Hat Enterprise Linux Real Time (v. 9) | Fixed | RHSA-2026:68570 |
| Red Hat Enterprise Linux Real Time for NFV (v. 10) | Fixed | RHSA-2026:68507 |
| Red Hat Enterprise Linux Real Time for NFV (v. 9) | Fixed | RHSA-2026:68570 |
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-2026-64175
- 2026-10-03 Alias added: GHSA-6wqh-xprc-m65r
- 2026-10-13 Affected versions changed · Red Hat
- 2026-10-16 CISA SSVC decision points changed
- 2026-10-19 Weakness changed · CISA ADP
- 2026-10-29 Affected versions changed · Red Hat
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-2026-64175 · CVE Program
- CVE-2026-64175 · NVD
- FIRST EPSS
- GHSA-6wqh-xprc-m65r · GitHub Advisory Database · CC BY 4.0
- CVE-2026-64175 · Red Hat security data · CC BY 4.0
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