CVEvulnerability

CVE-2026-64034

9.3 CRITICAL Published 2026-07-19 Modified 2026-10-19 Official page ↗
Status
Modified
Published
2026-07-19
Last modified
2026-10-19
Assigner
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
9.3 CRITICAL — CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Weaknesses
CWE-367

Description

In the Linux kernel, the following vulnerability has been resolved: net: mana: Fix TOCTOU double-fetch of hwc_msg_id from DMA buffer In mana_hwc_rx_event_handler(), resp->response.hwc_msg_id is read from DMA-coherent memory and bounds-checked, then mana_hwc_handle_resp() re-reads the same field from the same DMA buffer for test_bit() and pointer arithmetic. DMA-coherent memory is mapped uncacheable on x86 and is shared, unencrypted, in Confidential VMs (SEV-SNP/TDX), so each load goes directly to host-visible memory. A H/W can modify the value between the check and the use, bypassing the bounds validation. Fix this by reading hwc_msg_id exactly once using READ_ONCE() into a stack-local variable in mana_hwc_rx_event_handler(), and passing the validated value as a parameter to mana_hwc_handle_resp().

Affected configurations

• linux linux kernel (>= 5.13 < 5.15.209) • linux linux kernel (>= 5.16 < 6.1.175) • linux linux kernel (>= 6.2 < 6.6.142) • linux linux kernel (>= 6.7 < 6.12.92) • linux linux kernel (>= 6.13 < 6.18.34) • linux linux kernel (>= 6.19 < 7.0.11) • linux linux kernel 7.1

Related

Weakness · CWE (1)

  • CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition weakness

References