Vulnerabilities > CVE-2017-7905 - Use of Insufficiently Random Values vulnerability in GE products
Summary
A Weak Cryptography for Passwords issue was discovered in General Electric (GE) Multilin SR 750 Feeder Protection Relay, firmware versions prior to Version 7.47; SR 760 Feeder Protection Relay, firmware versions prior to Version 7.47; SR 469 Motor Protection Relay, firmware versions prior to Version 5.23; SR 489 Generator Protection Relay, firmware versions prior to Version 4.06; SR 745 Transformer Protection Relay, firmware versions prior to Version 5.23; SR 369 Motor Protection Relay, all firmware versions; Multilin Universal Relay, firmware Version 6.0 and prior versions; and Multilin URplus (D90, C90, B95), all versions. Ciphertext versions of user passwords were created with a non-random initialization vector leaving them susceptible to dictionary attacks. Ciphertext of user passwords can be obtained from the front LCD panel of affected products and through issued Modbus commands.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Brute Force In this attack, some asset (information, functionality, identity, etc.) is protected by a finite secret value. The attacker attempts to gain access to this asset by using trial-and-error to exhaustively explore all the possible secret values in the hope of finding the secret (or a value that is functionally equivalent) that will unlock the asset. Examples of secrets can include, but are not limited to, passwords, encryption keys, database lookup keys, and initial values to one-way functions. The key factor in this attack is the attackers' ability to explore the possible secret space rapidly. This, in turn, is a function of the size of the secret space and the computational power the attacker is able to bring to bear on the problem. If the attacker has modest resources and the secret space is large, the challenge facing the attacker is intractable. While the defender cannot control the resources available to an attacker, they can control the size of the secret space. Creating a large secret space involves selecting one's secret from as large a field of equally likely alternative secrets as possible and ensuring that an attacker is unable to reduce the size of this field using available clues or cryptanalysis. Doing this is more difficult than it sounds since elimination of patterns (which, in turn, would provide an attacker clues that would help them reduce the space of potential secrets) is difficult to do using deterministic machines, such as computers. Assuming a finite secret space, a brute force attack will eventually succeed. The defender must rely on making sure that the time and resources necessary to do so will exceed the value of the information. For example, a secret space that will likely take hundreds of years to explore is likely safe from raw-brute force attacks.
- Signature Spoofing by Key Recreation An attacker obtains an authoritative or reputable signer's private signature key by exploiting a cryptographic weakness in the signature algorithm or pseudorandom number generation and then uses this key to forge signatures from the original signer to mislead a victim into performing actions that benefit the attacker.
- Session Credential Falsification through Prediction This attack targets predictable session ID in order to gain privileges. The attacker can predict the session ID used during a transaction to perform spoofing and session hijacking.