CVE-2026-6665 (GCVE-0-2026-6665)

Vulnerability from cvelistv5 – Published: 2026-05-09 00:43 – Updated: 2026-05-12 03:55
VLAI
Title
PgBouncer buffer overflow in SCRAM
Summary
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.
Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-11 00:00 UTC
CWE
  • CWE-121 - Stack-based Buffer Overflow
Assigner
PostgreSQL CNA under the redhat root
CNA scorecard C 69/100 over 115 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
n/a PgBouncer Affected: 0 , < 1.25.2 (semver)
Credits
Thanks to HarutoKimura for finding and reporting this problem.
Show details on NVD website
To clipboard 

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