A vulnerability has been identified in SIMATIC CP 1242-7 V2 (incl. SIPLUS variants) (All versions < V3.4.29), SIMATIC CP 1243-1 (incl. SIPLUS variants) (All versions < V3.4.29), SIMATIC CP 1243-1 DNP3 (incl. SIPLUS variants) (All versions), SIMATIC CP 1243-1 IEC (incl. SIPLUS variants) (All versions < V3.4.29), SIMATIC CP 1243-7 LTE (All versions < V3.4.29), SIMATIC CP 1243-8 IRC (6GK7243-8RX30-0XE0) (All versions < V3.4.29), SIMATIC CP 1542SP-1 (6GK7542-6UX00-0XE0) (All versions < V2.3), SIMATIC CP 1542SP-1 IRC (6GK7542-6VX00-0XE0) (All versions < V2.3), SIMATIC CP 1543-1 (6GK7543-1AX00-0XE0) (All versions < V3.0.37), SIMATIC CP 1543SP-1 (6GK7543-6WX00-0XE0) (All versions < V2.3), SINAMICS S210 (6SL5...) (All versions >= V6.1 < V6.1 HF2), SIPLUS ET 200SP CP 1542SP-1 IRC TX RAIL (6AG2542-6VX00-4XE0) (All versions < V2.3), SIPLUS ET 200SP CP 1543SP-1 ISEC (6AG1543-6WX00-7XE0) (All versions < V2.3), SIPLUS ET 200SP CP 1543SP-1 ISEC TX RAIL (6AG2543-6WX00-4XE0) (All versions < V2.3), SIPLUS NET CP 1543-1 (6AG1543-1AX00-2XE0) (All versions < V3.0.37). The webserver implementation of the affected products does not correctly release allocated memory after it has been used. An attacker with network access could use this vulnerability to cause a denial-of-service condition in the webserver of the affected product.
A flaw named FragmentSmack was found in the way the Linux kernel handled reassembly of fragmented IPv4 and IPv6 packets. A remote attacker could use this flaw to trigger time and calculation expensive fragment reassembly algorithms by sending specially crafted packets which could lead to a CPU saturation and hence a denial of service on the system.
External References:
https://access.redhat.com/articles/3553061
https://www.kb.cert.org/vuls/id/641765
A fix is a merge commit in the Linux kernel tree:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c30f1fc041b74ecdb072dd44f858750414b8b19f
consisting of the following commits:
7969e5c40dfd04799d4341f1b7cd266b6e47f227 385114dec8a49b5e5945e77ba7de6356106713f4 fa0f527358bd900ef92f925878ed6bfbd51305cc