CVE-2026-6665

EUVD-2026-28877
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
8.1 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 28%
Affected Products (NVD)
VendorProductVersion
pgbouncerpgbouncer
𝑥
< 1.25.2
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
pgbouncer
bookworm
no-dsa
bullseye
postponed
bullseye (security)
vulnerable
forky
1.25.2-1
fixed
sid
1.25.2-1
fixed
trixie
1.24.1-1+deb13u2
fixed
Azure Linux logo
Azure Linux Releases
Azure Package
Release
pgbouncer
Azure Linux 3.0
0:1.25.2-1.azl3
fixed
Common Weakness Enumeration
References
https://www.pgbouncer.org/changelog.html#pgbouncer-125x