PatchSiren cyber security CVE debrief

CVE-2021-2154 Festo Didactic SE CVE debrief

CVE-2021-2154 is a denial-of-service issue described in the supplied Festo Didactic SE MES PC advisory corpus. The affected component is the underlying Oracle MySQL Server DML path, and successful exploitation can cause a hang or a repeatedly reproducible crash of the MySQL Server process. The advisory says the attack requires high privileges and network access, so this is not a low-skill or unauthenticated issue, but it can still disrupt availability if the exposed service is reachable.

Vendor: Festo Didactic SE
Product: MES PC
CVSS: MEDIUM 4.9
CISA KEV: Not listed in stored evidence
Original CVE published: 2024-02-27
Original CVE updated: 2026-01-27
Advisory published: 2024-02-27
Advisory updated: 2026-01-27

Who should care

Operators and maintainers of Festo Didactic SE MES PC deployments, especially environments that still rely on the affected XAMPP-based stack or the underlying MySQL service. Network and platform teams should also care if administrative MySQL access is reachable across internal segments.

Technical summary

The supplied CSAF source describes CVE-2021-2154 as a MySQL Server vulnerability in the Server:DML component affecting supported versions 5.7.33 and earlier. The CVSS vector is CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H, which aligns with the advisory language: the issue is network-reachable, requires high privileges, and primarily impacts availability. In the Festo advisory context, the remediation points to replacing XAMPP on MES PCs with Factory Control Panel and obtaining the current version from Festo technical support. The source corpus also indicates the advisory was republished by CISA on 2026-01-27, but the CVE itself was published on 2024-02-27.

Defensive priority

Medium priority: apply promptly on affected MES PC systems, but the need for high privileges lowers immediate exposure compared with unauthenticated remote flaws.

Recommended defensive actions

Identify MES PC systems that use the affected MySQL-backed stack or any XAMPP-based deployment referenced by the advisory.
Obtain and deploy the current Factory Control Panel release from Festo technical support, as listed in the vendor remediation.
Restrict administrative and MySQL network access to only trusted management hosts and segments.
Review privilege assignments so MySQL administrative access is limited to the minimum set of operators and services that require it.
Monitor for repeated MySQL service hangs, crashes, or restart loops on affected systems.
Confirm backups and restoration procedures are current before maintenance, since the impact is an availability loss rather than data exposure.

Evidence notes

This debrief is based only on the supplied CSAF/CISA advisory corpus and official links. The source description states: affected versions are 5.7.33 and prior; exploitation requires high privilege and network access via multiple protocols; impact is a hang or repeatable crash of MySQL Server. The supplied CVSS vector is CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H, score 4.9 (Medium). The source metadata ties the advisory to Festo Didactic SE MES PC and lists a remediation path to Factory Control Panel. Timing context: CVE published 2024-02-27; source modified 2026-01-27.

Official resources

The CVE was published on 2024-02-27 and the supplied source was last modified on 2026-01-27. This debrief reflects the supplied advisory corpus and official links only; it does not infer exploitability beyond the cited metadata.