CVE-2026-6664
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk49th percentile - higher than 49% of all known CVEs
Summary
An integer overflow in network packet parsing in PgBouncer before 1.25.2 bypasses a boundary check and can lead to a crash. An unauthenticated remote attacker can crash PgBouncer with a malformed SCRAM authentication packet.
Risk Assessment
The attack can cause PgBouncer to crash, resulting in unavailability of PostgreSQL database connections.
Recommendation
Upgrade PgBouncer to version 1.25.2 or later, which fixes the integer overflow.
Other vulnerabilities in PgBouncer
See all- CVE-2015-6817High
PgBouncer 1.6.x before 1.6.1, when configured with auth_user, allows remote attackers to gain login access as auth_user via an unknown username.
- CVE-2015-4054High
PgBouncer before 1.5.5 allows remote attackers to cause a denial of service (NULL pointer dereference and crash) by sending a password packet before a startup packet.
- CVE-2026-6667Medium
PgBouncer before 1.25.2 did not properly authorize the KILL_CLIENT admin command. Any user with access to the admin console could run it, instead of only users in the admin_users list.
- CVE-2026-6666Medium
In PgBouncer before version 1.25.2, a null pointer dereference could cause a crash if a server sends an error response without the SQLSTATE field.
- CVE-2026-6665High
The SCRAM code in PgBouncer before version 1.25.2 does not correctly check the return value of strlcat() when building the client-final-message. A malicious backend sending a server-final-message with a long nonce can trigger a stack overflow.
Original NVD description (English source)
An integer overflow in network packet parsing code in PgBouncer before 1.25.2 bypasses a boundary check and can lead to a crash. An unauthenticated remote attacker can crash PgBouncer with a malformed SCRAM authentication packet.