CVE-2026-6669
mediumpriority · track · 0EPSS 0.004 · 36 %ileDERUUSEPSS · scored 2026-10-27
Missing upper bound on the key derivation iteration count accepted during SCRAM authentication to a backend server in PgBouncer through 1.25.2 allows a malicious or compromised PostgreSQL backend to cause uncontrolled CPU consumption in PgBouncer. The resulting key derivation cannot be interrupted in frontend builds such as PgBouncer. Because PgBouncer serves all clients from a single process, one backend can in this way stop it from serving traffic for every other database and client it is pooling, so the failure of a single backend is not contained.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
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affected products (4)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-3529PgBouncer: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2026-09-22csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in PgBouncer ausnutzen, um einen Denial of Service Angriff durchzuführen.
- BIT-pgbouncer-2026-6669Unbounded SCRAM iteration count causes CPU exhaustion in PgBouncer2026-10-01vendor · osvUS
Missing upper bound on the key derivation iteration count accepted during SCRAM authentication to a backend server in PgBouncer through 1.25.2 allows a malicious or compromised PostgreSQL backend to cause uncontrolled CPU consumption in PgBouncer. The resulting key derivation cannot be interrupted in frontend builds such as PgBouncer. Because PgBouncer serves all clients from a single process, one backend can in this way stop it from serving traffic for every other database and client it is pooling, so the failure of a single backend is not contained.
also known as (1)
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sources
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references (1) nvd
External citations — patches, advisories, analysis.
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