The do_change_cipher_spec function in OpenSSL 0.9.6c to 0.9.6k, and 0.9.7a to 0.9.7c, allows remote attackers to cause a denial of service (crash) via a crafted SSL/TLS handshake that triggers a null dereference.

OpenSSL 0.9.6 before 0.9.6d does not properly handle unknown message types, which allows remote attackers to cause a denial of service (infinite loop), as demonstrated using the Codenomicon TLS Test Tool.

Heap-based buffer overflow in ASN.1 decoding library in Check Point VPN-1 products, when Aggressive Mode IKE is implemented, allows remote attackers to execute arbitrary code by initiating an IKE negotiation and then sending an IKE packet with malformed ASN.1 data.

Buffer overflow in the ISAKMP functionality for Check Point VPN-1 and FireWall-1 NG products, before VPN-1/FireWall-1 R55 HFA-03, R54 HFA-410 and NG FP3 HFA-325, or VPN-1 SecuRemote/SecureClient R56, may allow remote attackers to execute arbitrary code during VPN tunnel negotiation.

Stack-based buffer overflow in Check Point VPN-1 Server 4.1 through 4.1 SP6 and Check Point SecuRemote/SecureClient 4.1 through 4.1 build 4200 allows remote attackers to execute arbitrary code via an ISAKMP packet with a large Certificate Request packet.

Multiple format string vulnerabilities in HTTP Application Intelligence (AI) component in Check Point Firewall-1 NG-AI R55 and R54, and Check Point Firewall-1 HTTP Security Server included with NG FP1, FP2, and FP3 allows remote attackers to execute arbitrary code via HTTP requests that cause format string specifiers to be used in an error message, as demonstrated using the scheme of a URI.

Check Point FireWall-1 4.0 and 4.1 before SP5 allows remote attackers to obtain the IP addresses of internal interfaces via certain SecuRemote requests to TCP ports 256 or 264, which leaks the IP addresses in a reply packet.

The design of the Internet Key Exchange (IKE) protocol, when using Aggressive Mode for shared secret authentication, does not encrypt initiator or responder identities during negotiation, which may allow remote attackers to determine valid usernames by (1) monitoring responses before the password is supplied or (2) sniffing, as originally reported for FireWall-1 SecuRemote.

Check Point FireWall-1 4.1 and Next Generation (NG), with UserAuth configured to proxy HTTP traffic only, allows remote attackers to pass unauthorized HTTPS, FTP and possibly other traffic through the firewall.

Check Point FireWall-1 SecuRemote/SecuClient 4.0 and 4.1 allows clients to bypass the "authentication timeout" by modifying the to_expire or expire values in the client's users.C configuration file.