Horde IMP's AppleDouble MIME viewer writes an attacker-controlled attachment name into an HTML status block without escaping it. In lib/Mime/Viewer/Appledouble.php, _IMPrender() obtains the name of the data part with IMP_Contents::getPartName(), which returns the MIME part's own name parameter as supplied by the message, and passes it through sprintf into the text of an IMP_Mime_Status object. IMP_Mime_Status::__toString() concatenates each text entry directly into the surrounding table markup, so the value reaches the rendered page verbatim. A message crafted as multipart/appledouble whose data part carries markup in its name parameter therefore executes script in the context of any user who views it, and the payload persists in the mailbox. Exploitation requires no account on the target system, only the ability to send mail to a user. Version 7.2.0 escapes the value with htmlspecialchars(). The researcher additionally chains this flaw with the arbitrary file read of CVE-2026-58451, and reports that script running in an administrator's session can reach an application code-execution path.
Advisories
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Fixes
Solution
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Workaround
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References
History
Mon, 24 Aug 2026 15:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Horde IMP's AppleDouble MIME viewer writes an attacker-controlled attachment name into an HTML status block without escaping it. In lib/Mime/Viewer/Appledouble.php, _IMPrender() obtains the name of the data part with IMP_Contents::getPartName(), which returns the MIME part's own name parameter as supplied by the message, and passes it through sprintf into the text of an IMP_Mime_Status object. IMP_Mime_Status::__toString() concatenates each text entry directly into the surrounding table markup, so the value reaches the rendered page verbatim. A message crafted as multipart/appledouble whose data part carries markup in its name parameter therefore executes script in the context of any user who views it, and the payload persists in the mailbox. Exploitation requires no account on the target system, only the ability to send mail to a user. Version 7.2.0 escapes the value with htmlspecialchars(). The researcher additionally chains this flaw with the arbitrary file read of CVE-2026-58451, and reports that script running in an administrator's session can reach an application code-execution path. | |
| Title | Horde IMP before 7.2.0 Stored Cross-Site Scripting via AppleDouble Viewer Part Name | |
| First Time appeared |
Horde
Horde horde Imp |
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| Weaknesses | CWE-79 | |
| CPEs | cpe:2.3:a:horde:horde_imp:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Horde
Horde horde Imp |
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| References |
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| Metrics |
cvssV3_1
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Projects
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Status: PUBLISHED
Assigner: VulnCheck
Published:
Updated: 2026-08-24T14:53:43.219Z
Reserved: 2026-07-21T14:05:53.719Z
Link: CVE-2026-65053
No data.
Status : Received
Published: 2026-08-24T15:16:39.380
Modified: 2026-08-24T15:16:39.380
Link: CVE-2026-65053
No data.
OpenCVE Enrichment
No data.
Weaknesses