Authenticated denial of service via crafted project file
Published Sep 2, 2021 · Updated May 29, 2026
Out-of-bounds write in Schneider Electric Modicon controllers and PLC simulators allows remote authenticated users to interrupt service. Crafted project-file data processed during controller application updates causes an out-of-bounds memory write, but Schneider Electric does not identify the parser or function. Low-privileged network access to update the controller application is required; all listed product versions can be interrupted, with no documented confidentiality or integrity impact.
Summary
What happened
Out-of-bounds write in Schneider Electric Modicon controllers and PLC simulators allows remote authenticated users to interrupt service. Crafted project-file data processed during controller application updates causes an out-of-bounds memory write, but Schneider Electric does not identify the parser or function. Low-privileged network access to update the controller application is required; all listed product versions can be interrupted, with no documented confidentiality or integrity impact.
The record
- CVE
- CVE-2021-22791
- Published
- Sep 2, 2021
- Updated
- May 29, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T0814
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 2, 2021CVE publishedPublication date reported by the CVE source.
- May 29, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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Attacks
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Public exploit references
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Technologies
Your stack
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Your stack
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