CVE-2024-49948: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.3% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: net: add more sanity checks to qdisc_pkt_len_init() One path takes care of SKB_GSO_DODGY, assuming skb->len is bigger than hdr_len. virtio_net_hdr_to_skb() does not fully dissect TCP headers, it only make sure it is at least 20 bytes. It is possible for an user to provide a malicious 'GSO' packet, total length of 80 bytes. - 20 bytes of IPv4 header - 60 bytes TCP header - a small gso_size like 8 virtio_net_hdr_to_skb() would declare this packet as a normal GSO packet, because it would see 40 bytes of payload, bigger than gso_size. We need to make detect this case to not underflow qdisc_skb_cb(skb)->pkt_len.

Affected products

• Linux Linux Kernel: from 3.9, before 4.19.323 (fixed in 4.19.323); from 4.20, before 5.4.285 (fixed in 5.4.285); from 5.5, before 5.10.227 (fixed in 5.10.227); from 5.11, before 5.15.168 (fixed in 5.15.168); from 5.16, before 6.1.113 (fixed in 6.1.113); from 6.2, before 6.6.55 (fixed in 6.6.55); …

Published 2024-10-21. Last modified 2026-06-17.