MIME::Field::ParamVal versions before 5.521 for Perl allow one invalid Content-Type parameter to hide the parameters after it, including the multipart boundary.
Parameter parsing stops at the first parameter whose name it cannot read, such as x:y=1 or a name containing an 8-bit byte, and drops every parameter after it. When the boundary is among them, MIME::Parser keeps the multipart body as a single undecoded part without marking the parse as ambiguous.
Mail readers that skip the invalid parameter still find the boundary. A remote sender can hide an attachment from a filter that relies on ambiguous_content() while the recipient's mail client shows it.
CVSS
No CVSS.
References
Configurations
No configuration.
History
28 Oct 2026, 18:17
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-10-28 18:17
Updated : 2026-10-29 15:11
NVD link : CVE-2026-116264
Mitre link : CVE-2026-116264
CVE.ORG link : CVE-2026-116264
JSON object : View
Products Affected
No product.
CWE
CWE-436
Interpretation Conflict
