CVE-2026-74999: CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') in Roundcube Webmail
A stored cross-site scripting (XSS) vulnerability exists in Roundcube Webmail versions before 1.6.18 and 1.7.x before 1.7.3. The flaw occurs in the "Add to address book" feature, allowing malicious input to be improperly neutralized during web page generation. This vulnerability has a medium severity rating with a CVSS score of 5.4.
AI Analysis
Technical Summary
CVE-2026-74999 is a stored XSS vulnerability in Roundcube Webmail affecting versions prior to 1.6.18 and 1.7.3. The issue arises from improper neutralization of input in the "Add to address book" action, which can lead to execution of malicious scripts in the context of the victim's browser. The vulnerability requires low attack complexity and privileges with user interaction, and impacts confidentiality and integrity but not availability.
Potential Impact
Successful exploitation could allow an attacker to execute arbitrary scripts in the context of the victim's browser session, potentially leading to information disclosure or manipulation of user data within the webmail interface. The vulnerability does not impact system availability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Users should monitor Roundcube's official channels for updates and apply any released patches for versions prior to 1.6.18 and 1.7.3 once available. Until patched, cautious handling of address book entries and limiting user privileges may reduce risk.
CVE-2026-74999: CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') in Roundcube Webmail
Description
A stored cross-site scripting (XSS) vulnerability exists in Roundcube Webmail versions before 1.6.18 and 1.7.x before 1.7.3. The flaw occurs in the "Add to address book" feature, allowing malicious input to be improperly neutralized during web page generation. This vulnerability has a medium severity rating with a CVSS score of 5.4.
CVSS v3.1
Score 5.4medium
Affected software
pkg:github/roundcube/roundcubemailRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-74999 is a stored XSS vulnerability in Roundcube Webmail affecting versions prior to 1.6.18 and 1.7.3. The issue arises from improper neutralization of input in the "Add to address book" action, which can lead to execution of malicious scripts in the context of the victim's browser. The vulnerability requires low attack complexity and privileges with user interaction, and impacts confidentiality and integrity but not availability.
Potential Impact
Successful exploitation could allow an attacker to execute arbitrary scripts in the context of the victim's browser session, potentially leading to information disclosure or manipulation of user data within the webmail interface. The vulnerability does not impact system availability.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Users should monitor Roundcube's official channels for updates and apply any released patches for versions prior to 1.6.18 and 1.7.3 once available. Until patched, cautious handling of address book entries and limiting user privileges may reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-08-17T12:42:51.192Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a8309b6bf8831d539eb803b
Added to database: 08/17/2026, 13:16:38 UTC
Last enriched: 08/17/2026, 13:30:55 UTC
Last updated: 08/17/2026, 13:30:55 UTC
Views: 3
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