The SUSE Linux Enterprise 12 SP3 kernel was updated to receive various security and bugfixes.
The following security bugs were fixed:
- CVE-2019-10638: In the Linux kernel, a device could be tracked by an attacker using the IP ID values the kernel produces for connection-less protocols (e.g., UDP and ICMP). When such traffic was sent to multiple destination IP addresses, it was possible to obtain hash collisions (of indices to the counter array) and thereby obtain the hashing key (via enumeration). An attack may have been conducted by hosting a crafted web page that uses WebRTC or gQUIC to force UDP traffic to attacker-controlled IP addresses (bnc#1140575 1140577).
- CVE-2019-10639: The Linux kernel allowed Information Exposure (partial kernel address disclosure), that lead to a KASLR bypass. Specifically, it was possible to extract the KASLR kernel image offset using the IP ID values the kernel produces for connection-less protocols (e.g., UDP and ICMP). When such traffic is sent to multiple destination IP addresses, it was possible to obtain hash collisions (of indices to the counter array) and thereby obtain the hashing key (via enumeration). This key contains enough bits from a kernel address (of a static variable) so when the key is extracted (via enumeration), the offset of the kernel image is exposed. This attack could be carried out remotely, by the attacker forcing the target device to send UDP or ICMP (or certain other) traffic to attacker-controlled IP addresses. Forcing a server to send UDP traffic is trivial if the server is a DNS server. ICMP traffic is trivial if the server answers ICMP Echo requests (ping). For client targets, if the target visited the attacker's web page, then WebRTC or gQUIC could be used to force UDP traffic to attacker-controlled IP addresses. NOTE: this attack against KASLR became viable because IP ID generation was changed to have a dependency on an address associated with a network namespace (bnc#1140577).
-...