CVE-2026-42198
pgjdbc: Unbounded PBKDF2 iterations in SCRAM authentication allows CPU exhaustion DoS
Description
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.
How to fix CVE-2026-42198
To remediate CVE-2026-42198, upgrade the affected package to a fixed version below.
- —upgrade to 42.7.11 or later
- —no fix listed
- —upgrade to 42.7.11 or later
Is CVE-2026-42198 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- >= 42.2.0, < 42.7.11
- from 0
- >= 42.2.0, < 42.7.11
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |