Bug 2563060 (CVE-2026-116273)

Summary: CVE-2026-116273 perl-mime-tools: perl-mime-tools: Denial of Service via memory exhaustion from excessive message parts
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in perl-mime-tools. The parser does not enforce a default limit on the number of parts processed in a MIME (Multipurpose Internet Mail Extensions) message. A remote attacker could exploit this vulnerability by submitting a crafted message containing an excessive number of parts, leading to memory exhaustion and a Denial of Service (DoS).
 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: 2563416    
Bug Blocks:    

Description OSIDB Bzimport 2026-10-28 17:44:38 UTC 
MIME::Parser versions before 5.521 for Perl set no limit on the number of message parts by default, allowing memory exhaustion.

The max_parts option defaulted to -1, which disables the limit, so a parser created with default settings builds an entity for every part however many a message has.

Version 5.521 sets max_parts to 1000 and max_depth to 64 by default. Setting either to -1 still removes the limit.