Bug 2566810

Summary: CVE-2026-67242 rabbitmq-server: rabbitmq-server: Authentication bypass via improper validation of floating-point token expiration timestamps [fedora-all]
Product: [Fedora] Fedora Reporter: Mauro Matteo Cascella <mcascell>
Component: rabbitmq-serverAssignee: Peter Lemenkov <lemenkov>
Status: CLOSED CURRENTRELEASE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: lemenkov, rich
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["e0f9b8ea-eb41-4a0a-a409-2953a3f106ff"]}
Fixed In Version: rabbitmq-server-4.2.9 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-11-04 16:11:02 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: 2541506    

Description Mauro Matteo Cascella 2026-11-04 10:23:48 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.

RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.9 and 4.3.3, OAuth2 isinteger(Exp) guard skips token-expiry checks for float exp. validatetokenexpiry/1 (lines 208-214) and expirytimestamp/1 (138-144) both guard with 'when isinteger(Exp)' and fall through to ok/never for float values. josejwt:verify validates only the signature, not exp. With float exp, no expiry validation occurs anywhere in the If the IdP emits exp as a JSON float (RFC 7519 permits fractional NumericDate), both the login-time expiry check and the mid-connection disconnect timer are silently skipped , an already-expired token is accepted, and connections never time OAuth2 backend enabled IdP emits float exp (uncommon; mainstream IdPs emit integers) Attacker possesses a previously-valid signed. This issue is fixed in versions 4.2.9 and 4.3.3.

Comment 1 Peter Lemenkov 2026-11-04 15:44:14 UTC
This issue is fixed upstream in RabbitMQ 4.2.9 and 4.3.3. Fedora 45 and rawhide ship rabbitmq-server-4.3.7, and Fedora 44 ships rabbitmq-server-4.2.9, so both are already fixed.

The issue only affects 4.2.0 and later, so Fedora 43 (4.0.9) is not affected.

Comment 2 Peter Lemenkov 2026-11-04 16:11:02 UTC
Every supported Fedora release is fixed or not affected:
- Fedora 45 and rawhide: rabbitmq-server-4.3.7, fixed (upstream fix in 4.3.3)
- Fedora 44: rabbitmq-server-4.2.9, fixed (upstream fix in 4.2.9)
- Fedora 43: rabbitmq-server-4.0.9, not affected (the issue only affects 4.2.0 and later)