CVE-2026-116269: medium-severity vulnerability in MIME-tools
MIME::Field::ParamVal versions before 5.521 for Perl turn an RFC 2231 filename with a hyphenated language tag into an empty recommended filename
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.3epss 0.2%
MIME::Field::ParamVal versions before 5.521 for Perl turn an RFC 2231 filename with a hyphenated language tag into an empty recommended filename.
A parameter such as filename*=utf-8'en-US'payload.exe is converted to an encoded word with the language tag appended to the charset. The decoder strips the language suffix only when it is a single word, so it cannot resolve the charset UTF-8*EN-US and returns an empty string. The recommended_filename() method returns that empty string rather than falling back to the name parameter.
Other mail readers return payload.exe. A remote sender can get an attachment past a policy that checks file extensions on the recommended filename.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Affected products
MIME-toolsRelated CVEs — MIME-tools
In the same product, most dangerous first.
CVE-2026-116273HIGHMIME::Parser versions before 5.521 for Perl set no limit on the number of message parts by default, allowing memory exhaustionEPSS 0.3%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-2026-116266MEDIUMMIME::Head versions from 5.518 before 5.521 for Perl decode a partly encoded multipart boundary without flagging the parse as ambiguousEPSS 0.2%