Bug 2539635

Summary: CVE-2026-6669 pgbouncer: PgBouncer: Denial of Service via unbounded SCRAM iteration count [fedora-all]
Product: [Fedora] Fedora Reporter: Vladimir Vasilev <vvasilev>
Component: pgbouncerAssignee: Devrim Gündüz <devrim>
Status: ON_QA --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: devrim, negativo17, praiskup
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["a5869907-d5b7-4033-ada5-1492302a435b"]}
Fixed In Version: Doc Type: ---
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Clone Of: Environment:
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Documentation: --- CRM:
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On:    
Bug Blocks: 2539546    

Description Vladimir Vasilev 2026-09-23 18:31:37 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.

Missing upper bound on the key derivation iteration count accepted during SCRAM authentication to a backend server in PgBouncer through 1.25.2 allows a malicious or compromised PostgreSQL backend to cause uncontrolled CPU consumption in PgBouncer. The resulting key derivation cannot be interrupted in frontend builds such as PgBouncer. Because PgBouncer serves all clients from a single process, one backend can in this way stop it from serving traffic for every other database and client it is pooling, so the failure of a single backend is not contained.

Comment 1 Fedora Update System 2026-09-26 16:53:41 UTC
FEDORA-2026-851c3ccde8 (pgbouncer-1.26.0-1.fc45) has been submitted as an update to Fedora 45.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-851c3ccde8

Comment 2 Fedora Update System 2026-09-27 01:46:54 UTC
FEDORA-2026-851c3ccde8 has been pushed to the Fedora 45 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-851c3ccde8`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-851c3ccde8

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 3 Fedora Update System 2026-09-27 01:57:09 UTC
FEDORA-EPEL-2026-39a80c0763 has been pushed to the Fedora EPEL 10.4 testing repository.

You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-39a80c0763

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 4 Fedora Update System 2026-09-27 02:03:43 UTC
FEDORA-EPEL-2026-237c7e9b4d has been pushed to the Fedora EPEL 10.2 testing repository.

You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-237c7e9b4d

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 5 Fedora Update System 2026-09-27 02:06:31 UTC
FEDORA-2026-99030761e8 has been pushed to the Fedora 44 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-99030761e8`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-99030761e8

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 6 Fedora Update System 2026-09-27 02:16:34 UTC
FEDORA-EPEL-2026-62de33e876 has been pushed to the Fedora EPEL 9 testing repository.

You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-62de33e876

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 7 Fedora Update System 2026-09-27 02:29:59 UTC
FEDORA-2026-6197f5c17e has been pushed to the Fedora 43 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-6197f5c17e`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-6197f5c17e

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.