Entreprise française de cybersécurité depuis 2004
☎ 03 60 47 09 81 - info@securiteinfo.com
☎ 03 60 47 09 81 - info@securiteinfo.com
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, assumingskb->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 8virtio_net_hdr_to_skb() would declare this packet as a normalGSO packet, because it would see 40 bytes of payload,bigger than gso_size.We need to make detect this case to not underflowqdisc_skb_cb(skb)->pkt_len.
No PoCs from references.
- https://github.com/w4zu/Debian_security