Bug 2553069

Summary:	CVE-2026-107350 pgbouncer: pgbouncer: Privilege escalation via secondary startup message during SCRAM authentication [fedora-all]
Product:	[Fedora] Fedora	Reporter:	Vladimir Vasilev <vvasilev>
Component:	pgbouncer	Assignee:	Devrim Gündüz <devrim>
Status:	NEW ---	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	high	Docs Contact:
Priority:	high
Version:	rawhide	CC:	devrim, negativo17, praiskup
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["9d688105-3e12-4de8-b0b6-a5bdd46cd531"]}
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Doc Text:		Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	2552733

Description Vladimir Vasilev 2026-10-15 07:18:19 UTC

Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

Improper authentication in PgBouncer 1.17.0 through 1.26.0 allows a remote attacker who knows the password of a user listed in auth_file to log in as any other user that authenticates using SCRAM, including PgBouncer admin users and backend superusers. A second StartupMessage sent during SCRAM authentication against a non-existent database is not rejected and switches the user being logged in as, while the SCRAM exchange is still verified against the keys of the first user.