A weakness has been identified in ulisesbocchio jasypt-spring-boot up to 3.0.5/4.0.4. Affected by this vulnerability is the function getSecretKeySaltGenerator of the file jasypt-spring-boot/src/main/java/com/ulisesbocchio/jasyptspringboot/encryptor/SimpleGCMConfig.java of the component Password Hash Handler. Executing a manipulation can lead to use of a one-way hash with a predictable salt. The attack can be launched remotely. The attack requires a high level of complexity. The exploitation appears to be difficult. The exploit has been made available to the public and could be used for attacks. The project was informed of the problem early through an issue report but has not responded yet.
Weakness
The product uses a one-way cryptographic hash against an input that should not be reversible, such as a password, but the product does not also use a salt as part of the input.
Extended Description
This makes it easier for attackers to pre-compute the hash value using dictionary attack techniques such as rainbow tables. It should be noted that, despite common perceptions, the use of a good salt with a hash does not sufficiently increase the effort for an attacker who is targeting an individual password, or who has a large amount of computing resources available, such as with cloud-based services or specialized, inexpensive hardware. Offline password cracking can still be effective if the hash function is not expensive to compute; many cryptographic functions are designed to be efficient and can be vulnerable to attacks using massive computing resources, even if the hash is cryptographically strong. The use of a salt only slightly increases the computing requirements for an attacker compared to other strategies such as adaptive hash functions. See CWE-916 for more details.
Potential Mitigations
- Use an adaptive hash function that can be configured to change the amount of computational effort needed to compute the hash, such as the number of iterations (“stretching”) or the amount of memory required. Some hash functions perform salting automatically. These functions can significantly increase the overhead for a brute force attack compared to intentionally-fast functions such as MD5. For example, rainbow table attacks can become infeasible due to the high computing overhead. Finally, since computing power gets faster and cheaper over time, the technique can be reconfigured to increase the workload without forcing an entire replacement of the algorithm in use.
- Some hash functions that have one or more of these desired properties include bcrypt [REF-291], scrypt [REF-292], and PBKDF2 [REF-293]. While there is active debate about which of these is the most effective, they are all stronger than using salts with hash functions with very little computing overhead.
- Note that using these functions can have an impact on performance, so they require special consideration to avoid denial-of-service attacks. However, their configurability provides finer control over how much CPU and memory is used, so it could be adjusted to suit the environment’s needs.