CVE-2026-68373
In the Linux kernel, the following vulnerability has been resolved: wifi: at76c50x-usb: avoid length underflow in at76_guess_freq() at76_guess_freq() checks only that the received frame is at least a bare 802.11 header (24 bytes) before subtracting the…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.28%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: wifi: at76c50x-usb: avoid length underflow in at76_guess_freq() at76_guess_freq() checks only that the received frame is at least a bare 802.11 header (24 bytes) before subtracting the fixed management-body offset: len -= el_off; For both beacon and probe response frames, el_off is 36. If the frame is shorter than el_off, subtracting it causes the calculated IE length to wrap. The length is eventually passed to cfg80211_find_elem_match() as a very large unsigned value, so the element walk runs beyond the RX skb. This path is reached from at76_rx_tasklet() while scanning. If the device delivers a truncated beacon or probe response, the oversized IE length causes an out-of-bounds read during scanning. Skip the IE lookup if the frame does not reach the variable elements, before subtracting el_off.
- CVSS 3.1
- 8.1 HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- EPSS
- 0.28% probability · 20th percentile
- CISA KEV
- Not listed
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/4875680d1703f56afa6257ba30244f2fb44ed205
- https://git.kernel.org/stable/c/61a799ffd1e5a4fd3702d547828b7ff3d161468e
- https://git.kernel.org/stable/c/b406f33d234f98c8b310fdab5cbb492d85e98e49
- https://git.kernel.org/stable/c/bcde7249d45f52f994a9872bedf45994472ade77
- https://git.kernel.org/stable/c/cb831aff2f850f72bc5ff5ad77d0a70bb5a84061
- https://git.kernel.org/stable/c/e165a1d295e7e814e13b0f92c86e5d48309509ce
- https://git.kernel.org/stable/c/f742d9c98b5c504fc9e6744eef13a721c2aea486
- https://git.kernel.org/stable/c/fb1b50ab699211e777dca5ccfb648788b6a6e519
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.