CVE-2026-116273

MIME::Parser versions before 5.521 for Perl set no limit on the number of message parts by default, allowing memory exhaustion

Published Oct 28, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

Vendor Solution

Upgrade to MIME-tools 5.521 or later.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Important

Type Values Removed Values Added
First Time appeared Perl
Perl mime::parser
Vendors & Products Perl
Perl mime::parser
Type Values Removed Values Added
Description 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.
Title MIME::Parser versions before 5.521 for Perl set no limit on the number of message parts by default, allowing memory exhaustion
Weaknesses CWE-1188
CWE-770
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
CPANSec
Published
Updated
Nov 5, 2026, 8:43 PM
Reserved
Oct 25, 2026, 6:05 PM
Status
Awaiting Analysis
Published
Oct 28, 2026, 6:17 PM
Modified
Nov 5, 2026, 9:18 PM
Severity
Important
Public date
Oct 28, 2026, 5:34 PM