Two high-severity vulnerabilities affecting OpenPLC_V3 were disclosed in CISA ICS advisory ICSA-25-345-10, exposing industrial control environments to unauthorized access and credential compromise. CVE-2026-28205 is an insecure default initialization flaw (CWE-1188) that could allow a remote attacker to bypass authentication through an API and gain access to the system, with the CVSS v4 vector indicating network reachability, low attack complexity, and no required privileges or user interaction.
A second issue, CVE-2026-35556, involves plaintext password storage (CWE-256) in OpenPLC_V3, creating a path for attackers to recover credentials and access sensitive information. The vulnerability record also carries a network-exploitable CVSS v4 profile with low attack complexity and high potential impact to confidentiality, integrity, and availability, underscoring the risk to operators using the platform in ICS environments.

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The vulnerability records included references to a CISA ICS advisory for the OpenPLC_V3 issues, including advisory ICSA-25-345-10 for CVE-2026-35556. The initial records also added severity and weakness classification details for both CVEs.
A new vulnerability entry for CVE-2026-35556 was received by ICS-CERT affecting OpenPLC_V3. The vulnerability involves plaintext password storage, which could enable credential retrieval and access to sensitive information.
A new vulnerability entry for CVE-2026-28205 was received by ICS-CERT at DHS affecting OpenPLC_V3. The flaw is an insecure default initialization issue that could allow authentication bypass through an API and unauthorized system access.
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