pgjdbc 42.2.042.7.10 DoS via SCRAM PBKDF2
CVE-2026-42198 Published on April 29, 2026
pgjdbc: Unbounded PBKDF2 iterations in SCRAM authentication allows CPU exhaustion DoS
pgjdbc is an open source postgresql JDBC Driver. From version 42.2.0 to before version 42.7.11, pgjdbc is vulnerable to a client-side denial of service during SCRAM-SHA-256 authentication. A malicious server can instruct the driver to perform SCRAM authentication with a very large iteration count. With a large enough value, the client spends an unbounded amount of CPU time inside PBKDF2 before authentication can fail. A single attempt ties up a CPU core. Repeated or concurrent attempts exhaust client CPU and can wedge connection pools. In affected versions, loginTimeout did not fully mitigate this problem. When loginTimeout expired, the caller could stop waiting, but the worker thread performing the connection attempt could continue running and burning CPU inside the SCRAM PBKDF2 computation. This issue has been patched in version 42.7.11.
Vulnerability Analysis
CVE-2026-42198 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.
Weakness Type
Allocation of Resources Without Limits or Throttling
The software allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.