TI-2026-74363 Aliases CVE-2026-107349

Infinite loop in PgBouncer startup options parameter handling

LOW 39CWE-400Published 2026-10-14 · Updated 2026-10-16

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-400.

Summary

PgBouncer versions from 1.20.0 through 1.26.0 contain an infinite loop in the handling of startup parameters, caused by an empty parameter name in the options parameter of a StartupMessage (CWE-835). An unauthenticated remote attacker can send such a message to make the process loop forever. Because PgBouncer serves all clients from a single process, a CPU core is saturated and PgBouncer stops responding to all clients until it is restarted.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00404 34th percentileScored 2026-11-07

Fix Fixed PgBouncer: 1.26.1Red Hat: 1 advisory

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	PgBouncer	1.20.0 to before 1.26.1	1.26.1	Patch available	CNA

PgBouncer Vendor— Affected 1.20.0 to before 1.26.1 Fixed in 1.26.1 Patch available CNA

Remediation

Upgrade PgBouncer to version 1.26.1, which fixes this flaw. Red Hat advisory RHSA-2026:83843, released 2026-10-16, fixes it in Red Hat Hardened Images.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Fix · CNA PgBouncer Fixed in 1.26.1

Red Hat 1 advisory

RHSA-2026:83843 Released 2026-10-16 · Red Hat rating Important
Red Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images pgbouncer-1.26.1-1.hum1@aarch64, pgbouncer-1.26.1-1.hum1@s390x, pgbouncer-1.26.1-1.hum1@src +1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2026-10-14
PgBouncer 1.26.1
3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW
Other records, highest priority first
- TI-2026-74364 PgBouncer authentication bypass lets attackers log in as other usersPriority MEDIUM 40
- TI-2026-74362 Integer overflow in PgBouncer buffer growth causes infinite loopPriority LOW 27
Show all 3 records →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

Product	Status	Plan or fix
Red Hat Hardened Images	Fixed	RHSA-2026:83843

Timeline

2026-10-15 Threatist record created from CVE-2026-107349
2026-10-16 Priority changed: MEDIUM → LOW
2026-10-16 Affected versions changed · Red Hat
2026-10-16 CVSS score added · Red Hat
2026-10-18 CISA SSVC decision points changed
2026-10-18 Fix available: RHSA-2026:83843 · Red Hat
2026-10-18 Fix available: Red Hat Hardened Images · Red Hat

References

Other 1

https://www.pgbouncer.org/changelog.html

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences