CVE-2026-31780

HIGH

wifi: wilc1000: fix u8 overflow in SSID scan buffer size calculation

Title source: cna
STIX 2.1

Description

In the Linux kernel, the following vulnerability has been resolved: wifi: wilc1000: fix u8 overflow in SSID scan buffer size calculation The variable valuesize is declared as u8 but accumulates the total length of all SSIDs to scan. Each SSID contributes up to 33 bytes (IEEE80211_MAX_SSID_LEN + 1), and with WILC_MAX_NUM_PROBED_SSID (10) SSIDs the total can reach 330, which wraps around to 74 when stored in a u8. This causes kmalloc to allocate only 75 bytes while the subsequent memcpy writes up to 331 bytes into the buffer, resulting in a 256-byte heap buffer overflow. Widen valuesize from u8 to u32 to accommodate the full range.

Scores

CVSS v3 7.8
EPSS 0.0001
EPSS Percentile 2.5%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-787
Status published
Products (20)
Linux/Linux < 4.2
Linux/Linux 4.2
Linux/Linux 5.10.253 - 5.10.*
Linux/Linux 5.15.203 - 5.15.*
Linux/Linux 6.1.168 - 6.1.*
Linux/Linux 6.12.81 - 6.12.*
Linux/Linux 6.18.22 - 6.18.*
Linux/Linux 6.19.12 - 6.19.*
Linux/Linux 6.6.134 - 6.6.*
Linux/Linux 7.0
... and 10 more
Published May 01, 2026
Tracked Since May 01, 2026