The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

Jonathan Looney discovered that the TCP_SKB_CB(skb)->tcp_gso_segs value was subject to an integer overflow in the Linux kernel when handling TCP Selective Acknowledgments (SACKs). A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit 3b4929f65b0d8249f19a50245cd88ed1a2f78cff.

Jonathan Looney discovered that the TCP retransmission queue implementation in tcp_fragment in the Linux kernel could be fragmented when handling certain TCP Selective Acknowledgment (SACK) sequences. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit f070ef2ac66716357066b683fb0baf55f8191a2e.

The default configuration of Avaya Secure Access Link (SAL) Gateway 1.5, 1.8, and 2.0 contains certain domain names in the Secondary Core Server URL and Secondary Remote Server URL fields, which allows remote attackers to obtain sensitive information by leveraging administrative access to these domain names, as demonstrated by alarm and log information.