CVE-2026-116265 (GCVE-0-2026-116265)

Vulnerability from cvelistv5 – Published: 2026-10-28 17:32 – Updated: 2026-11-05 20:18
VLAI
Title
MIME::Field::ParamVal versions before 5.521 for Perl do not flag an ambiguous multipart boundary written as RFC 2231 continuations
Summary
MIME::Field::ParamVal versions before 5.521 for Perl do not flag an ambiguous multipart boundary written as RFC 2231 continuations. The boundary ambiguity checks look only at a plain boundary= parameter, and a boundary split into RFC 2231 sections (boundary*0=, boundary*1= and so on) is joined after they have run. A repeated section number is concatenated rather than reported as a duplicate. From version 5.518, an encoded word or trailing whitespace in such a boundary also goes unflagged, although multipart_boundary() decodes or strips it. A remote sender can make MIME::Parser split a message on a different boundary than other mail readers, hiding an attachment from a filter that relies on ambiguous_content() while the recipient's mail client shows it.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-05 20:18 UTC
CWE
  • CWE-436 - Interpretation Conflict
Assigner
CPANSec CNA under the redhat root
CNA scorecard C 61/100 over 355 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Affected: 0 , < 5.521 (custom)
Show details on NVD website
To clipboard 

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