Vulnerability in Roundcube Webmail
CVE-2026-35542
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. The remote image blocking feature can be bypassed via a crafted background attribute of a BODY element in an e-mail message. This may lead to information disclosure or access-control bypass.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.005 (42.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 42.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001
Affected products
- Roundcube Webmail — versions 0, 1.6.0
Weakness classification (CWE)
References
- roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14 (Vendor Advisory)
- github.com/roundcube/roundcubemail/releases/tag/1.7-rc5 (Release Notes)
- github.com/roundcube/roundcubemail/commit/fd0e98178db5c73eaa93d005b561874923f9b… (Patch)
- github.com/roundcube/roundcubemail/releases/tag/1.6.14 (Release Notes)
- github.com/roundcube/roundcubemail/commit/fde14d01adc9f37893cd82b635883e516ed45… (Patch)
- github.com/roundcube/roundcubemail/releases/tag/1.5.14 (Release Notes)
- github.com/roundcube/roundcubemail/commit/e052328e3dc75f13adc2e314eaa4096ac2108… (Patch)
Frequently asked questions
- What is CVE-2026-35542?
- CVE-2026-35542 is a medium-severity vulnerability in Roundcube Webmail, classified under Incorrect Resource Transfer Between Spheres. CVSS score: 5.3/10. Published 2026-04-03.
- How severe is CVE-2026-35542?
- Medium severity. CVSS v3 base score is 5.3 out of 10.