Bug 2540017

Summary: CVE-2026-93990 mingw-expat: Expat: XML Injection via Malformed UTF-16 Input [fedora-all]
Product: [Fedora] Fedora Reporter: Srikanth Balasubramanian <sbalasub>
Component: mingw-expatAssignee: Richard W.M. Jones <rjones>
Status: ON_QA --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: rawhideCC: manisandro, rjones
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["c8dc2477-9048-4495-96c1-f472693b71a3"]}
Fixed In Version: Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 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: 2538967    

Description Srikanth Balasubramanian 2026-09-24 11:35:11 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.

Expat through 2.8.4 fails to validate low surrogates following high surrogates in UTF-16 input, allowing malformed UTF-16 sequences to be accepted. Attackers can craft UTF-16 encoded XML with lone high surrogates that consume following code units, hiding markup characters from the parser and enabling XML injection attacks.

Comment 1 Fedora Update System 2026-10-17 09:16:09 UTC
FEDORA-2026-2d09775040 (mingw-expat-2.8.5-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-2d09775040

Comment 2 Fedora Update System 2026-10-17 09:16:10 UTC
FEDORA-2026-457e7c0fba (mingw-expat-2.8.5-1.fc45) has been submitted as an update to Fedora 45.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-457e7c0fba

Comment 3 Fedora Update System 2026-10-18 01:51:29 UTC
FEDORA-2026-457e7c0fba 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-2026-457e7c0fba`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-457e7c0fba

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

Comment 4 Fedora Update System 2026-10-18 02:46:08 UTC
FEDORA-2026-2d09775040 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-2026-2d09775040`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-2d09775040

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

Comment 5 Fedora Update System 2026-10-24 17:25:26 UTC
FEDORA-2026-86ef30a678 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-2026-86ef30a678`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-86ef30a678

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

Comment 6 Fedora Update System 2026-10-24 18:15:19 UTC
FEDORA-2026-3c5a339682 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-2026-3c5a339682`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-3c5a339682

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