8.8
HIGH CVSS 3.1
CVE-2026-74997
Roundcube Webmail Markasjunk Plugin Remote Code Execution Vulnerability
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.

INFO

Published Date :

Aug. 17, 2026, 1:16 p.m.

Last Modified :

Aug. 17, 2026, 3:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-74997 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Roundcube webmail
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH 8254265b-2729-46b6-b9e3-3dfca2d5bfca
CVSS 3.1 HIGH [email protected]
CVSS 3.1 HIGH MITRE-CVE
Solution
Update Roundcube Webmail to version 1.6.18 or 1.7.3 to fix RCE.
  • Update Roundcube Webmail to 1.6.18 or later.
  • Update Roundcube Webmail to 1.7.3 or later.
  • Ensure the markasjunk plugin is disabled if not needed.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-74997 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-74997 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-74997 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 17, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-74997', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-17T14:34:16.294775Z'}
  • New CVE Received by [email protected]

    Aug. 17, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Roundcube', 'product': 'Webmail', 'versions': [{'status': 'affected', 'version': '1.6.0', 'lessThan': '1.6.18', 'versionType': 'semver'}, {'status': 'affected', 'version': '1.7.0', 'lessThan': '1.7.3', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}]
    Added 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.
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-78
    Added Reference https://github.com/roundcube/roundcubemail/commit/14044f843cfacbe78b042f659e379d6b4497aa7c
    Added Reference https://github.com/roundcube/roundcubemail/commit/495d211638f222336b20f4744545c53712426c2a
    Added Reference https://github.com/roundcube/roundcubemail/commit/b8f90e28a46d42e79a69568cba897f8f4223d9cd
    Added Reference https://github.com/roundcube/roundcubemail/releases/tag/1.6.18
    Added Reference https://github.com/roundcube/roundcubemail/releases/tag/1.7.3
    Added Reference https://roundcube.net/news/2026/08/09/security-updates-1.6.18-and-1.7.3
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.