OpenSSL Updates Fix DTLS DoS and Memory-Safety Flaws

OpenSSL released versions 1.0.1u and 1.0.2i to correct multiple vulnerabilities affecting earlier releases. The flaws include DTLS denial-of-service issues: CVE-2016-2181, which lets an attacker advance a connection’s replay-protection window with an unauthenticated future-epoch record and cause valid packets to be discarded, and CVE-2016-2179, which can retain unnecessary out-of-order handshake fragments and consume roughly 1.5 MB of memory per DTLS connection. CVE-2016-6302 can also crash servers using a custom SHA-512 TLS session-ticket HMAC callback through an integer underflow and out-of-bounds read.

The updates additionally address memory-safety defects in certificate and utility processing. CVE-2016-2182 is an out-of-bounds write in BN_bn2dec() caused by unchecked BN_div_word() failures when handling oversized BIGNUM values, while CVE-2016-2180 can cause an out-of-bounds read when the openssl ts utility parses crafted time-stamp data containing large OIDs. CVE-2016-6306 involves a small out-of-bounds read in certificate-message handling when client authentication is enabled. Red Hat issued fixes for affected RHEL 6 and 7 packages, including RHSA-2016:1940, with later JBoss Core Services updates for CVE-2016-2182.