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TI-2026-44240 Aliases CVE-2026-61815GHSA-36h5-qg4p-q2qf

zbateson/mail-mime-parser has CRLF header injection via attachment filename

Priority LOW 37CWE-93Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.

Summary

zbateson/mail-mime-parser is a mail mime parser alternative to PHP's imap* functions and Pear libraries for reading messages in Internet Message Format RFC 822. Prior to version 3.0.6 and 4.0.2, CRLF (carriage-return / line-feed) header injection (CWE-93) affecting any application that uses this library to build or forward MIME messages with an attacker-influenced attachment filename. Attachment filenames are interpolated into the `Content-Type` and `Content-Disposition` header values without stripping CR/LF, so a filename containing `\r\n` serializes as one or more additional, attacker-controlled header lines (for example a forged `Bcc:` that silently exfiltrates a copy of the outgoing message). The untrusted filename can come directly from parsed inbound mail, so no local construction is required — an application that re-attaches or re-sends a parsed filename is exposed. Versions 3.0.6 and 4.0.2 patch the issue. Versions 1.x and 2.x are also affected but are end-of-life and will not receive patches; users on those lines should upgrade to a fixed release. If upgrading is not immediately possible, strip CR and LF from any filename before passing it to attachment APIs, and from the result of getFilename() before reusing it in a constructed message — e.g. preg_replace('/[\r\n]+/', ' ', $filename).

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00178 7th percentileScored 2026-11-07
Fix Fixed mail-mime-parser (zbateson): 3.0.6, 4.0.2zbateson/mail-mime-parser (Packagist): 3.0.6, 4.0.2

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
zbatesonmail-mime-parserbefore 3.0.6; 4.0.0 to before 4.0.23.0.6, 4.0.2Patch availableCNA
—zbateson/mail-mime-parser (Packagist)before 3.0.63.0.6Patch availableGHSA-36h5-qg4p-q2qf
—zbateson/mail-mime-parser (Packagist)4.0.0 to before 4.0.24.0.2Patch availableGHSA-36h5-qg4p-q2qf
  • mail-mime-parser Vendorzbateson Affected before 3.0.6; 4.0.0 to before 4.0.2 Fixed in 3.0.6, 4.0.2 Patch available CNA
  • zbateson/mail-mime-parser (Packagist) Vendor— Affected before 3.0.6 Fixed in 3.0.6 Patch available GHSA-36h5-qg4p-q2qf
  • zbateson/mail-mime-parser (Packagist) Vendor— Affected 4.0.0 to before 4.0.2 Fixed in 4.0.2 Patch available GHSA-36h5-qg4p-q2qf

Remediation

  • Fix · CNA mail-mime-parser (zbateson) Fixed in 3.0.6, 4.0.2
  • Fix · GHSA-36h5-qg4p-q2qf zbateson/mail-mime-parser (Packagist) Fixed in 3.0.6 Advisory →
  • Fix · GHSA-36h5-qg4p-q2qf zbateson/mail-mime-parser (Packagist) Fixed in 4.0.2 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-61815
  2. 2026-10-03 Alias added: GHSA-36h5-qg4p-q2qf
  3. 2026-10-05 CISA SSVC decision points changed

References

  • TI-2026-44241 zbateson/mail-mime-parser has uncontrolled resource consumption (CPU/memory DoS) parsing untrusted MIME CVSS 3.1HIGH 7.5
  • TI-2026-85057 CRLF header injection in zbateson mail-mime-parser message builders CVSS 4.0MEDIUM 6.9

Sources