CVE-2026-31780
Published: May 6, 2026Last modified: May 6, 2026
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.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.8 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.168-r0) |
| 25 LTS | linux-lts | Fixed (6.12.81-r0) | |
| Stream | linux-lts | Fixed (6.12.85-r0) |
References
- https://git.kernel.org/stable/c/0c7f21d8bd2f93998b72b7a7f93152336aeca4dd
- https://git.kernel.org/stable/c/34a23fd9ddd683a03c7e8cc0ceded3e59e354b99
- https://git.kernel.org/stable/c/549f02d8ec94d39092ab6d9b103d0d6783a4b024
- https://git.kernel.org/stable/c/9907ac9b9a18b92fc34b9e4cb9e10f208dc1d3f7
- https://git.kernel.org/stable/c/bfbddeadd4779651403035ee177ae2f22f9f5521
- https://git.kernel.org/stable/c/c97b2a00059608592ad0d86fbb813a4f8cf9464b
- https://git.kernel.org/stable/c/d049e56b1739101d1c4d81deedb269c52a8dbba0
- https://git.kernel.org/stable/c/d8388614de613c28eeb659c10115060a83739924