Horizon Alert
Summary of the vulnerability and why it matters
This vulnerability in PgBouncer could allow a malicious server to cause a stack overflow by sending a specially crafted message. This could disrupt the availability of database connections managed by PgBouncer.
- Can affect availability.
- Requires interaction with a backend server.
Attack Path
How an attacker could exploit the issue
A malicious backend database server can exploit this flaw to trigger a stack overflow in PgBouncer by sending a crafted SCRAM server-final-message. This could allow the attacker to crash the PgBouncer service or potentially achieve remote code execution if the overflow is exploitable.
- Requires attacker control of a backend.
- Targets PgBouncer SCRAM authentication.
- Long nonce triggers overflow.
Live Threat
Current exploitation, exposure, and threat context
This SCRAM stack overflow vulnerability in PgBouncer is unlikely to be weaponized by external attackers. The complexity of needing to control or impersonate a backend database server to trigger the vulnerability, combined with PgBouncer's typical deployment within secure internal networks, significantly reduces its appeal for widespread exploitation.
- Requires backend control.
- Network deployment limits reach.
- No public exploit available.
Priority actions
Operational Fix
Recommended remediation, mitigation, and detection steps
Prioritize updating PgBouncer to version 1.25.2 or later to address the critical SCRAM stack overflow vulnerability. If immediate patching is not feasible, focus on isolating affected services to prevent exploitation by malicious backends.
- Update PgBouncer to 1.25.2.
- Isolate affected services if patching is delayed.
- Monitor for unexpected connections or authentication failures.
