CVE-2026-6665

The SCRAM code in PgBouncer before 1.25.2 did not check the return value of strlcat() correctly when building the contents of the SCRAM client-final-message. A malicious backend that sends a SCRAM server-final-message with a long nonce can trigger a stack overflow.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.pgbouncer.org/changelog.html#pgbouncer-125x	Release Notes

Configurations

Configuration 1 (hide)

cpe:2.3:a:pgbouncer:pgbouncer:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-09 01:16

Updated : 2026-07-24 08:10

NVD link : CVE-2026-6665

Mitre link : CVE-2026-6665

CVE.ORG link : CVE-2026-6665

JSON object : View

Products Affected

pgbouncer

pgbouncer

CWE

CWE-121

Stack-based Buffer Overflow

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