by Kastro
Paper/Archive/CVE-2026-6665

CVE-2026-6665

PostgreSQL — PgBouncer buffer overflow in SCRAM

EPSS 0.4%CVSS 9.8
critical.is priorityof 100
36
CVSS 9.8 (NVD)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 31.1.311 × 206.2No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
PgBouncer< 1.25.21.25.2CNA

Scores by source

NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
PostgreSQL (CNA)8.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

refpgbouncer.org/changelog.html#pgbouncer-125x