CVE-2026-74997: CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') in Roundcube Webmail
In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, the cmd_learn driver of the markasjunk plugin is subject to remote code execution via crafted placeholder replacement values. This issue only affects Roundcube instances using the markasjunk plugin with its cmd_learn driver.
AI Analysis
Technical Summary
Roundcube Webmail versions 1.6.0 and 1.7.0 are vulnerable to an OS command injection (CWE-78) in the cmd_learn driver of the markasjunk plugin. An attacker can exploit crafted placeholder replacement values to execute arbitrary commands remotely. This vulnerability is present only if the markasjunk plugin with the cmd_learn driver is used. The CVSS 3.1 score is 8.8, indicating high severity with network attack vector, low attack complexity, requiring low privileges, no user interaction, and impacts confidentiality, integrity, and availability.
Potential Impact
Successful exploitation allows remote attackers to execute arbitrary OS commands on the affected Roundcube Webmail server, potentially leading to full system compromise, data theft, or service disruption. The impact affects confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, disabling the markasjunk plugin or specifically its cmd_learn driver can mitigate the risk. Monitor vendor channels for updates and apply patches promptly once released.
CVE-2026-74997: CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') in Roundcube Webmail
Description
In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, the cmd_learn driver of the markasjunk plugin is subject to remote code execution via crafted placeholder replacement values. This issue only affects Roundcube instances using the markasjunk plugin with its cmd_learn driver.
CVSS v3.1
Score 8.8high
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
Roundcube Webmail versions 1.6.0 and 1.7.0 are vulnerable to an OS command injection (CWE-78) in the cmd_learn driver of the markasjunk plugin. An attacker can exploit crafted placeholder replacement values to execute arbitrary commands remotely. This vulnerability is present only if the markasjunk plugin with the cmd_learn driver is used. The CVSS 3.1 score is 8.8, indicating high severity with network attack vector, low attack complexity, requiring low privileges, no user interaction, and impacts confidentiality, integrity, and availability.
Potential Impact
Successful exploitation allows remote attackers to execute arbitrary OS commands on the affected Roundcube Webmail server, potentially leading to full system compromise, data theft, or service disruption. The impact affects confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, disabling the markasjunk plugin or specifically its cmd_learn driver can mitigate the risk. Monitor vendor channels for updates and apply patches promptly once released.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-08-17T12:37:44.639Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a8309b6bf8831d539eb802c
Added to database: 08/17/2026, 13:16:38 UTC
Last enriched: 08/17/2026, 13:26:23 UTC
Last updated: 08/18/2026, 02:41:00 UTC
Views: 10
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