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.
https://www.vulncheck.com/advisories/horde-imp-path-traversal-via-compose-php-img-src
https://www.horde.org/apps/imp
https://github.com/horde/imp/releases/tag/v7.0.1
https://github.com/horde/imp/pull/85
https://github.com/horde/imp/commit/fba972fab72ee6871e5d56e6390bee38593085de
Published: 2026-07-01
Updated: 2026-07-01
Base Score: 6.8
Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:N/A:N
Severity: Medium
Base Score: 6.5
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Severity: Medium
Base Score: 7.1
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Severity: High