Description
Horde IMP before 7.0.1 contains a path traversal vulnerability in lib/Compose.php that allows authenticated attackers to read arbitrary files from the server filesystem by embedding traversal sequences after a CKEditor path prefix in img src URLs. Attackers can bypass the stripos() prefix validation by appending sequences such as traversal segments after the matching prefix, causing file_get_contents() to read sensitive files whose contents are then exfiltrated as MIME parts in outgoing email; unauthenticated exploitation is also achievable via CSRF against an active authenticated session.
Problem types
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Product status
Any version before 7.0.1
Credits
evan
VulnCheck
References
seclists.org/fulldisclosure/2026/Jul/8
github.com/horde/imp/releases/tag/v7.0.1 (Release Notes)
github.com/horde/imp/pull/85 (Fix PR)
github.com/...ommit/fba972fab72ee6871e5d56e6390bee38593085de (Fix Commit)
www.horde.org/apps/imp (Project Webpage)
www.vulncheck.com/...-path-traversal-via-compose-php-img-src
blog.evan.lat/posts/CVE-2026-58451/ (Researcher Disclosure)