In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: cyw: fix heap overflow on a short auth frame brcmf_notify_auth_frame_rx() takes the frame length from the firmware event and copies the frame body with the management header offset subtracted: u32 mgmt_frame_len = e->datalen - sizeof(struct brcmf_rx_mgmt_data); ... memcpy(&mgmt_frame->u, frame, mgmt_frame_len - offsetof(struct ieee80211_mgmt, u)); The only length check is e->datalen >= sizeof(*rxframe), so mgmt_frame_len can be anything from 0 up. offsetof(struct ieee80211_mgmt, u) is 24. When mgmt_frame_len is below that, the subtraction wraps as an unsigned value to a huge length. The memcpy then runs far past the kzalloc'd buffer. A malicious or malfunctioning AP can make the frame short during the external SAE auth exchange, so this is a remotely triggered heap overflow. Reject frames shorter than the management header offset before the copy.
History

Sat, 15 Aug 2026 08:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-120

Sat, 15 Aug 2026 06:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: cyw: fix heap overflow on a short auth frame brcmf_notify_auth_frame_rx() takes the frame length from the firmware event and copies the frame body with the management header offset subtracted: u32 mgmt_frame_len = e->datalen - sizeof(struct brcmf_rx_mgmt_data); ... memcpy(&mgmt_frame->u, frame, mgmt_frame_len - offsetof(struct ieee80211_mgmt, u)); The only length check is e->datalen >= sizeof(*rxframe), so mgmt_frame_len can be anything from 0 up. offsetof(struct ieee80211_mgmt, u) is 24. When mgmt_frame_len is below that, the subtraction wraps as an unsigned value to a huge length. The memcpy then runs far past the kzalloc'd buffer. A malicious or malfunctioning AP can make the frame short during the external SAE auth exchange, so this is a remotely triggered heap overflow. Reject frames shorter than the management header offset before the copy.
Title wifi: brcmfmac: cyw: fix heap overflow on a short auth frame
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-08-15T05:51:34.730Z

Reserved: 2026-08-09T03:40:39.898Z

Link: CVE-2026-72003

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-15T06:20:53.557

Modified: 2026-08-15T06:20:53.557

Link: CVE-2026-72003

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-15T08:30:05Z