CVE-2022-28733: GNU GRUB2

High severity, CVSS 8.1. EPSS: 1.3% chance of exploitation in the next 30 days.

Integer underflow in grub_net_recv_ip4_packets; A malicious crafted IP packet can lead to an integer underflow in grub_net_recv_ip4_packets() function on rsm->total_len value. Under certain circumstances the total_len value may end up wrapping around to a small integer number which will be used in memory allocation. If the attack succeeds in such way, subsequent operations can write past the end of the buffer.

Affected products

• GNU GRUB2: from 2.00, before 2.06-3 (fixed in 2.06-3)

Published 2023-07-20. Last modified 2026-06-17.