CVE-2026-107349 Infinite loop on empty option name in startup options parameter in PgBouncer
An unauthenticated remote attacker can cause a denial of service in PgBouncer by sending a startup message with an empty option name, leading to an infinite loop.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-107349?
CVE-2026-107349 is a high-severity denial of service vulnerability in PgBouncer, published on 14 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An infinite loop in PgBouncer 1.20.0 through 1.26.0 allows an unauthenticated remote attacker to cause a denial of service. A StartupMessage whose options parameter contains an empty parameter name, such as "-c=", makes the ignore_startup_parameters list lookup loop forever. Because PgBouncer serves all clients from a single process, this saturates a CPU core and makes PgBouncer unresponsive to all clients until the process is restarted.
Which versions are affected by CVE-2026-107349?
1 open source package ship an affected version, including pgbouncer.
| Package | Affected | Fixed in |
|---|---|---|
pgbouncer Bitnami | From 1.20.0 | 1.26.1 |
How do I fix CVE-2026-107349?
Upgrade pgbouncer to 1.26.1 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-107349 being exploited?
There is no known exploitation of CVE-2026-107349 in the wild and no public exploit code.
Sources
Also known as AZL-108192, BIT-pgbouncer-2026-107349, DEBIAN-CVE-2026-107349, ECHO-7592-aec9-5cd1, GHSA-h8cj-p2h5-hm79, UBUNTU-CVE-2026-107349.