PatchSiren cyber security CVE debrief
CVE-2020-16233 Unknown Vendor CVE debrief
CVE-2020-16233 is a high-severity information disclosure vulnerability affecting CodeMeter versions prior to 7.10 as described in the CISA-republished Festo advisory. A specially crafted packet could trigger CodeMeter to send back packets containing data from the heap, creating a confidentiality risk for environments that rely on Festo Automation Suite and related CODESYS components. The source remediation guidance focuses on obtaining patched CODESYS releases from the official CODESYS website and keeping the Festo Automation Suite connector updated.
- Vendor
- Unknown Vendor
- Product
- FESTO
- CVSS
- HIGH 7.5
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-02-26
- Original CVE updated
- 2026-03-17
- Advisory published
- 2026-02-26
- Advisory updated
- 2026-03-17
Who should care
Organizations using Festo Automation Suite, CODESYS Development System, or CodeMeter in engineering, OT, or industrial automation environments should review this immediately, especially where these components are installed on workstations that handle sensitive configuration, project, or device data. Security teams responsible for industrial control systems should also care because the advisory is published through CISA and references software commonly used in OT workflows.
Technical summary
The advisory states that an attacker can send a specially crafted packet that may cause CodeMeter (all versions prior to 7.10) to send back packets containing heap data. The CVSS vector provided is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N, indicating network-based attack conditions, no privileges required, no user interaction, and high confidentiality impact. The source advisory ties the issue to Festo Automation Suite deployments that include CODESYS components and recommends using patched CODESYS releases and updated Festo Automation Suite connector packages.
Defensive priority
High. This is remotely reachable, low-complexity, and confidentiality-impacting, with direct relevance to industrial software environments. Prioritize any exposed or broadly deployed Festo Automation Suite / CODESYS / CodeMeter installations, then validate patch status and versioning across engineering endpoints.
Recommended defensive actions
- Identify systems running Festo Automation Suite, CODESYS Development System, or CodeMeter and confirm whether CodeMeter is older than 7.10.
- Upgrade to the latest patched CODESYS version obtained directly from the official CODESYS website, following vendor installation and update guidance.
- If using Festo Automation Suite, apply the latest FAS updates and ensure the connector is current.
- Review deployments of Festo Automation Suite versions earlier than 2.8.0.138 and verify how CODESYS is installed on each system.
- Monitor official CODESYS and Festo advisories for follow-on updates and remediation guidance.
- Limit exposure of OT/engineering systems to untrusted networks where feasible, and use segmentation and defense-in-depth controls around affected hosts.
Evidence notes
The supplied CISA CSAF source states: "An attacker could send a specially crafted packet that could have CodeMeter (All versions prior to 7.10) send back packets containing data from the heap." The same source includes remediation guidance to download patched CODESYS versions from the official CODESYS website and to keep the Festo Automation Suite connector updated. The advisory metadata points to Festo Automation Suite and CODESYS rather than a generic FESTO product label, so vendor/product attribution should be treated as low confidence and reviewed against the source advisory.
Official resources
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CVE-2020-16233 CVE record
CVE.org
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CVE-2020-16233 NVD detail
NVD
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Source item URL
cisa_csaf
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CISA CSAF republication of a Festo advisory on 2026-02-26, with a republication update on 2026-03-17. The source corpus does not indicate exploitation in the wild.