Bug 2563411

Summary:	CVE-2026-116270 perl-MIME-tools: perl-MIME-tools: Denial of Service via memory exhaustion from crafted MIME headers [fedora-rawhide]
Product:	[Fedora] Fedora	Reporter:	Marian Rehak <mrehak>
Component:	perl-MIME-tools	Assignee:	Paul Howarth <paul>
Status:	CLOSED ERRATA	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	high	Docs Contact:
Priority:	high
Version:	rawhide	CC:	paul, perl-devel
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["4ee8c977-8fd8-4402-be68-f1799cb2abb1"]}
Fixed In Version:	perl-MIME-tools-5.522-1.fc45 perl-MIME-tools-5.522-1.fc44 perl-MIME-tools-5.522-1.fc43	Doc Type:	---
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2026-11-06 01:15:17 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:	2563052

Description Marian Rehak 2026-10-29 15:06:22 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.

MIME::Words versions before 5.521 for Perl allow memory exhaustion via repeated "=?" sequences in decode_mimewords.

For each "=?" that does not start a complete encoded word, decode_mimewords appends an error message containing the whole input string to $@. A boundary of 8,000 "=?" pairs (16,000 bytes) adds 8,000 copies of itself to $@, about 128 MB.

From version 5.518, MIME::Parser decodes every multipart boundary this way, so a remote sender can exhaust the memory of the parsing process with one Content-Type header.

Comment 1 Fedora Update System 2026-10-30 08:33:00 UTC

FEDORA-2026-51fdfb7476 (perl-MIME-tools-5.522-1.fc45) has been submitted as an update to Fedora 45.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-51fdfb7476

Comment 2 Fedora Update System 2026-10-30 08:34:20 UTC

FEDORA-2026-0e79d6ad13 (perl-MIME-tools-5.522-1.fc44) has been submitted as an update to Fedora 44.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-0e79d6ad13

Comment 3 Fedora Update System 2026-10-30 08:35:26 UTC

FEDORA-2026-a415b3bf48 (perl-MIME-tools-5.522-1.fc43) has been submitted as an update to Fedora 43.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-a415b3bf48

Comment 4 Fedora Update System 2026-11-06 01:15:17 UTC

FEDORA-2026-51fdfb7476 (perl-MIME-tools-5.522-1.fc45) has been pushed to the Fedora 45 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 5 Fedora Update System 2026-11-06 01:25:19 UTC

FEDORA-2026-0e79d6ad13 (perl-MIME-tools-5.522-1.fc44) has been pushed to the Fedora 44 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 6 Fedora Update System 2026-11-06 01:50:10 UTC

FEDORA-2026-a415b3bf48 (perl-MIME-tools-5.522-1.fc43) has been pushed to the Fedora 43 stable repository.
If problem still persists, please make note of it in this bug report.