CVE-2026-48846
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk33th percentile - higher than 33% of all known CVEs
Summary
In Roundcube Webmail 1.6.x before 1.6.16 and 1.7.x before 1.7.1, the remote image blocking feature can be bypassed via a crafted CSS var() value in an e-mail message, which may lead to information disclosure or access-control bypass.
Risk Assessment
An attacker can bypass remote image blocking, potentially enabling email tracking (web beacon) or data leakage through requests to external servers.
Recommendation
Upgrade Roundcube to version 1.6.16, 1.7.1 or later. Consider additional protections such as HTML content filtering.
Other vulnerabilities in Roundcube
See all- CVE-2016-9920High
In Roundcube versions before 1.1.7 and 1.2.x before 1.2.3, the lack of SMTP server configuration and the enabling of the sendmail program does not properly restrict the use of custom envelope-from addresses on the sendmail command line. This allows remote authenticated users to execute arbitrary code via a modified HTTP request that sends a crafted e-mail message.
- CVE-2015-8770High
Directory traversal vulnerability in the set_skin function in rcmail_output_html.php in Roundcube before 1.0.8 and 1.1.x before 1.1.4 allows remote authenticated users with certain permissions to read arbitrary files or possibly execute arbitrary code via a .. (dot dot) in the _skin parameter to index.php.
Original NVD description (English source)
In Roundcube Webmail 1.6.x before 1.6.16 and 1.7.x before 1.7.1, the remote image blocking feature can be bypassed via a crafted CSS var() value in an e-mail message, which may lead to information disclosure or access-control bypass.