CVE-2026-116273: high-severity vulnerability in MIME-tools
MIME::Parser versions before 5.521 for Perl set no limit on the number of message parts by default, allowing memory exhaustion
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.3%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
MIME-toolsRelated CVEs — MIME-tools
In the same product, most dangerous first.
CVE-2026-116270HIGHMIME::Words versions before 5.521 for Perl allow memory exhaustion via repeated "=?" sequences in decode_mimewordsEPSS 0.3%CVE-2026-116268HIGHMIME::Field::ParamVal versions before 5.521 for Perl allow CPU exhaustion via unclosed comments in header parametersEPSS 0.3%CVE-2026-116267HIGHMIME::Parser versions before 5.521 for Perl allow memory exhaustion via indented error messages from a truncated, deeply nested messageEPSS 0.3%CVE-2026-116272MEDIUMMIME::Field::ParamVal versions before 5.521 for Perl do not flag a duplicate boundary parameter whose name contains a nested commentEPSS 0.2%CVE-2026-116269MEDIUMMIME::Field::ParamVal versions before 5.521 for Perl turn an RFC 2231 filename with a hyphenated language tag into an empty recommended filenameEPSS 0.2%CVE-2026-116266MEDIUMMIME::Head versions from 5.518 before 5.521 for Perl decode a partly encoded multipart boundary without flagging the parse as ambiguousEPSS 0.2%