Bug 2459283

Summary: CVE-2026-40170 ngtcp2: ngtcp2: Denial of service via stack buffer overflow during QUIC handshake [fedora-all]
Product: [Fedora] Fedora Reporter: Marco Benatto <mbenatto>
Component: ngtcp2Assignee: Petr Menšík <pemensik>
Status: CLOSED ERRATA QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: rawhideCC: asn, crypto-team, dns-sig, pemensik
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["443e0f07-54d3-45d9-99ce-47b2ca786efc"]}
Fixed In Version: ngtcp2-1.22.1-1.fc43 ngtcp2-1.22.1-1.fc44 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-04-28 00:59:16 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2459061    

Description Marco Benatto 2026-04-17 20:15:13 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.

Comment 1 Fedora Update System 2026-04-20 14:29:40 UTC
FEDORA-2026-705eb9cf95 (ngtcp2-1.22.1-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-705eb9cf95

Comment 2 Fedora Update System 2026-04-20 14:31:04 UTC
FEDORA-2026-a0f25484e9 (ngtcp2-1.22.1-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-a0f25484e9

Comment 3 Fedora Update System 2026-04-22 10:02:04 UTC
FEDORA-2026-a0f25484e9 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-a0f25484e9`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-a0f25484e9

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

Comment 4 Fedora Update System 2026-04-22 11:24:13 UTC
FEDORA-2026-705eb9cf95 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-2026-705eb9cf95`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-705eb9cf95

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

Comment 5 Fedora Update System 2026-04-28 00:59:16 UTC
FEDORA-2026-a0f25484e9 (ngtcp2-1.22.1-1.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 6 Fedora Update System 2026-04-28 01:33:52 UTC
FEDORA-2026-705eb9cf95 (ngtcp2-1.22.1-1.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.