Bug 2427895 - CVE-2025-12543 resteasy: Undertow HTTP Server Fails to Reject Malformed Host Headers Leading to Potential Cache Poisoning and SSRF [fedora-43]
Summary: CVE-2025-12543 resteasy: Undertow HTTP Server Fails to Reject Malformed Host ...
Keywords:
Status: CLOSED NOTABUG
Alias: None
Product: Fedora
Classification: Fedora
Component: resteasy
Version: 43
Hardware: Unspecified
OS: Unspecified
high
high
Target Milestone: ---
Assignee: Endi Sukma Dewata
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard: {"flaws": ["3d485e40-cb75-420e-b979-3...
Depends On:
Blocks: CVE-2025-12543
TreeView+ depends on / blocked
 
Reported: 2026-01-08 11:50 UTC by Abhishek Raj
Modified: 2026-09-24 09:27 UTC (History)
6 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2026-09-24 09:27:42 UTC
Type: ---
Embargoed:

Attachments (Terms of Use)

Description Abhishek Raj 2026-01-08 11:50:44 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.

The following link provides references to all essential vulnerability management information. If something is wrong or missing, please contact a member of PSIRT.
https://spaces.redhat.com/display/PRODSEC/Vulnerability+Management+-+Essential+Documents+for+Engineering+Teams
Comment 1 Marco Fargetta 2026-09-24 09:27:42 UTC 
The problem is in the library undertow-core used inside several resteasy modules (resteasy-bom, resteasy-jaxrs-testsuite, resteasy-wadl-undertow-connector, server-adapters and tjws).All the modules using the specified library are disabled.
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