SSH Communications Security Tectia Server

The SSH USERAUTH CHANGE REQUEST feature in SSH Tectia Server 6.0.4 through 6.0.20, 6.1.0 through 6.1.12, 6.2.0 through 6.2.5, and 6.3.0 through 6.3.2 on UNIX and Linux, when old-style password authentication is enabled, allows remote attackers to bypass authentication via a crafted session involving entry of blank passwords, as demonstrated by a root login session from a modified OpenSSH client with an added input_userauth_passwd_changereq call in sshconnect2.c.

SSH Tectia Client and Server before 6.4.19 on Windows have weak key generation. ConnectSecure on Windows is affected.

SSH Tectia Client and Server before 6.4.19 on Windows allow local privilege escalation. ConnectSecure on Windows is affected.

SSH Tectia Server 5.0.0 (A, F, and T), when allowing host-based authentication only, allows users to log in with the wrong credentials.

ssh-signer in SSH Tectia Client and Server 5.x before 5.2.4, and 5.3.x before 5.3.6, on Unix and Linux allows local users to gain privileges via unspecified vectors.

Unquoted Windows search path vulnerability in multiple SSH Tectia products, including Client/Server/Connector 5.0.0 and 5.0.1 and Client/Server before 4.4.5, and Manager 2.12 and earlier, when running on Windows, might allow local users to gain privileges via a malicious program file under "Program Files" or its subdirectories.

SSH Tectia Client and Server before 6.4.19 on Windows allow local privilege escalation in nonstandard conditions. ConnectSecure on Windows is affected.

SSH Tectia Client/Server/Connector 5.1.0 and earlier, Manager 2.2.0 and earlier, and other products, when using an RSA key with exponent 3, removes PKCS-1 padding before generating a hash, which allows remote attackers to forge a PKCS #1 v1.5 signature that is signed by that RSA key and prevents Tectia from correctly verifying X.509 and other certificates that use PKCS #1, a similar issue to CVE-2006-4339.

SSH Tectia Server 4.3.1 and earlier, and SSH Secure Shell for Windows Servers, uses insecure permissions when generating the Secure Shell host identification key, which allows local users to access the key and spoof the server.

SSH Tectia Server for IBM z/OS before 5.4.0 uses insecure world-writable permissions for (1) the server pid file, which allows local users to cause arbitrary processes to be stopped, or (2) when _BPX_BATCH_UMASK is missing from the environment, creates HFS files with insecure permissions, which allows local users to read or modify these files and have other unknown impact.

Error handling in the SSH protocol in (1) SSH Tectia Client and Server and Connector 4.0 through 4.4.11, 5.0 through 5.2.4, and 5.3 through 5.3.8; Client and Server and ConnectSecure 6.0 through 6.0.4; Server for Linux on IBM System z 6.0.4; Server for IBM z/OS 5.5.1 and earlier, 6.0.0, and 6.0.1; and Client 4.0-J through 4.3.3-J and 4.0-K through 4.3.10-K; and (2) OpenSSH 4.7p1 and possibly other versions, when using a block cipher algorithm in Cipher Block Chaining (CBC) mode, makes it easier for remote attackers to recover certain plaintext data from an arbitrary block of ciphertext in an SSH session via unknown vectors.

Race condition in SSH Tectia Server 4.0.3 and 4.0.4 for Unix, when the password change plugin (ssh-passwd-plugin) is enabled, allows local users to obtain the server's private key.