Bug 2494183

Summary: CVE-2026-12246 nsd: Out of bounds stack write with crafted APL RR [fedora-all]
Product: [Fedora] Fedora Reporter: Marco Benatto <mbenatto>
Component: nsdAssignee: Paul Wouters <paul.wouters>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: rawhideCC: drjohnson1, me, paul.wouters
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["ccba9b95-ac72-4018-8be3-bf58c0975e2b"]}
Fixed In Version: nsd-4.15.0-1.el10_3 nsd-4.15.0-1.el10_2 nsd-4.15.0-1.fc44 nsd-4.15.0-1.fc43 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-08-03 00:25:25 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: 2491589    

Description Marco Benatto 2026-06-29 13:48:08 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.

NSD version 4.14.0 introduced a bug where a specially crafted APL RR, with an adflength larger than permitted for the address family will overwrite the stack when the zone is written to disk, with a maximum of 111 attacker controlled bytes.

Even though the data is from a configured primary inside NSD's trust boundary, we do consider the risk significant enough for multi-tenant secondary DNS deployments, where a primary could introduce the rogue APL with the secondary not noticing or only after the fact.

Comment 1 Fedora Update System 2026-07-25 09:34:49 UTC
FEDORA-EPEL-2026-484870f7f9 (nsd-4.15.0-1.el10_3) has been submitted as an update to Fedora EPEL 10.3.
https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-484870f7f9

Comment 2 Fedora Update System 2026-07-25 09:35:10 UTC
FEDORA-2026-0b77a23312 (nsd-4.15.0-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-0b77a23312

Comment 3 Fedora Update System 2026-07-26 01:25:34 UTC
FEDORA-EPEL-2026-484870f7f9 has been pushed to the Fedora EPEL 10.3 testing repository.

You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2026-484870f7f9

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

Comment 4 Fedora Update System 2026-07-26 01:34:59 UTC
FEDORA-EPEL-2026-6030526353 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-2026-6030526353

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

Comment 5 Fedora Update System 2026-07-26 01:35:06 UTC
FEDORA-2026-0b77a23312 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-2026-0b77a23312`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-0b77a23312

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

Comment 6 Fedora Update System 2026-07-26 01:56:07 UTC
FEDORA-2026-d86ace09cb 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-d86ace09cb`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-d86ace09cb

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

Comment 7 Fedora Update System 2026-08-03 00:25:25 UTC
FEDORA-EPEL-2026-484870f7f9 (nsd-4.15.0-1.el10_3) has been pushed to the Fedora EPEL 10.3 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 8 Fedora Update System 2026-08-03 00:35:56 UTC
FEDORA-EPEL-2026-6030526353 (nsd-4.15.0-1.el10_2) has been pushed to the Fedora EPEL 10.2 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 9 Fedora Update System 2026-08-03 00:44:51 UTC
FEDORA-2026-d86ace09cb (nsd-4.15.0-1.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 10 Fedora Update System 2026-08-03 01:05:04 UTC
FEDORA-2026-0b77a23312 (nsd-4.15.0-1.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.