CVE-2026-98184

wifi: mwifiex: prevent authentication frame length truncation

Published Oct 6, 2026 CVSS 3.1 · 7.0 High EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

wifi: mwifiex: prevent authentication frame length truncation

mwifiex_cfg80211_authenticate() derives the authentication frame length
from req->ie_len and req->auth_data_len, both of type size_t, but stores
it in a u16.

NL80211_ATTR_AUTH_DATA only has a minimum length policy. Since nla_len is
a u16, a single attribute can carry up to 65531 bytes of payload, so the
sum can exceed U16_MAX before it is assigned to pkt_len. The truncated
pkt_len determines the skb frame area, while the copy length remains
req->auth_data_len - 4, resulting in a heap buffer overflow.

For example, with auth_data_len equal to 65510 and no IEs, the sum is
65546. It is truncated to 10 and then reduced by four to 6. The driver
appends only six bytes to the skb with skb_put(), but then copies 65506
user-provided bytes into the authentication body.

Reaching this path requires CAP_NET_ADMIN in the user namespace owning
the network namespace, an up station netdev, and a suitable BSS/SAE
authentication request.

Compute the length in size_t, reject values that cannot be represented by
the firmware's u16 frame length field, and only then assign it to pkt_len.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-4850-1 linux-6.12 security update
Debian DSA Debian DSA DSA-6568-1 linux security update
Ubuntu USN Ubuntu USN USN-9019-1 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-9020-1 Linux kernel vulnerabilities
History
Type Values Removed Values Added
Weaknesses CWE-119
CWE-680
Type Values Removed Values Added
Weaknesses CWE-787
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

threat_severity

Moderate

Type Values Removed Values Added
Weaknesses CWE-119
CWE-680
Type Values Removed Values Added
Weaknesses CWE-120
CWE-190
CWE-680
Type Values Removed Values Added
Weaknesses CWE-120
CWE-190
CWE-680
Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: wifi: mwifiex: prevent authentication frame length truncation mwifiex_cfg80211_authenticate() derives the authentication frame length from req->ie_len and req->auth_data_len, both of type size_t, but stores it in a u16. NL80211_ATTR_AUTH_DATA only has a minimum length policy. Since nla_len is a u16, a single attribute can carry up to 65531 bytes of payload, so the sum can exceed U16_MAX before it is assigned to pkt_len. The truncated pkt_len determines the skb frame area, while the copy length remains req->auth_data_len - 4, resulting in a heap buffer overflow. For example, with auth_data_len equal to 65510 and no IEs, the sum is 65546. It is truncated to 10 and then reduced by four to 6. The driver appends only six bytes to the skb with skb_put(), but then copies 65506 user-provided bytes into the authentication body. Reaching this path requires CAP_NET_ADMIN in the user namespace owning the network namespace, an up station netdev, and a suitable BSS/SAE authentication request. Compute the length in size_t, reject values that cannot be represented by the firmware's u16 frame length field, and only then assign it to pkt_len.
Title wifi: mwifiex: prevent authentication frame length truncation
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Oct 19, 2026, 9:15 AM
Reserved
Sep 25, 2026, 10:25 AM
Status
Received
Published
Oct 6, 2026, 9:18 AM
Modified
Oct 19, 2026, 10:18 AM
Severity
Moderate
Public date
Oct 6, 2026, 12:00 AM