Profinet-IO (PNIO) stack versions prior V06.00 do not properly limit internal resource allocation when multiple legitimate diagnostic package requests are sent to the DCE-RPC interface. This could lead to a denial of service condition due to lack of memory for devices that include a vulnerable version of the stack.

The security vulnerability could be exploited by an attacker with network access to an affected device. Successful exploitation requires no system privileges and no user interaction. An attacker could use the vulnerability to compromise the availability of the device.

An excessive resource consumption flaw was found in the way the Linux kernel's networking subsystem processed TCP segments. If the Maximum Segment Size (MSS) of a TCP connection was set to low values, such as 48 bytes, it can leave as little as 8 bytes for the user data, which significantly increases the Linux kernel's resource (CPU, Memory, and Bandwidth) utilization. A remote attacker could use this flaw to cause a denial of service (DoS) by repeatedly sending network traffic on a TCP connection with low TCP MSS.

An integer overflow flaw was found in the way the Linux kernel's networking subsystem processed TCP Selective Acknowledgment (SACK) segments. While processing SACK segments, the Linux kernel's socket buffer (SKB) data structure becomes fragmented. Each fragment is about TCP maximum segment size (MSS) bytes. To efficiently process SACK blocks, the Linux kernel merges multiple fragmented SKBs into one, potentially overflowing the variable holding the number of segments. A remote attacker could use this flaw to crash the Linux kernel by sending a crafted sequence of SACK segments on a TCP connection with small value of TCP MSS, resulting in a denial of service (DoS).