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PatchSiren cyber security CVE debrief

CVE-2023-1728 Fernus Informatics CVE debrief

CVE-2023-1728 is a critical vulnerability in Fernus Learning Management Systems (LMS) involving unrestricted upload of a file with a dangerous type. The issue can lead to OS command injection and Server Side Include (SSI) injection, and the CVSS v3.1 score is 9.8 (critical). NVD lists affected Fernus LMS versions as those before 23.04.03. Because the flaw is network exploitable, requires no privileges, and needs no user interaction, exposed LMS deployments should be treated as urgent remediation targets.

Vendor
Fernus Informatics
Product
LMS
CVSS
CRITICAL 9.8
CISA KEV
Not listed in stored evidence
Original CVE published
2023-04-04
Original CVE updated
2024-11-21
Advisory published
2023-04-04
Advisory updated
2024-11-21

Who should care

Fernus LMS administrators, application owners, security operations teams, and incident responders should prioritize this issue if any LMS instance is reachable over the network or accepts file uploads.

Technical summary

The NVD record describes an unrestricted file upload weakness that permits dangerous file types to be uploaded into Fernus LMS. The reported impact includes OS command injection and SSI injection. The supplied NVD vector is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, indicating remote exploitation with no authentication or user interaction and severe confidentiality, integrity, and availability impact. Vulnerable versions are those before 23.04.03.

Defensive priority

Critical. Prioritize immediate patching or isolation of affected Fernus LMS instances, especially if the platform is internet-facing or accepts user uploads.

Recommended defensive actions

  • Upgrade Fernus Learning Management Systems to version 23.04.03 or later as soon as possible.
  • Identify every deployed LMS instance, including test and forgotten systems, and verify whether any are running a version before 23.04.03.
  • If immediate upgrading is not possible, restrict access to upload features and place the application behind strong network controls until remediation is complete.
  • Review logs and application storage for unexpected or high-risk uploads, followed by any signs of command execution or SSI-related behavior.
  • After remediation, validate that upload handling enforces safe file-type controls and that the application is monitored for abuse of upload workflows.

Evidence notes

All claims are drawn from the supplied CVE record and NVD metadata. The vulnerability description explicitly states unrestricted upload of a dangerous file type with OS command injection and SSI injection impact. The affected-version boundary is provided in the NVD CPE criteria as endExcluding 23.04.03. The CVSS vector and score are taken from the supplied source data. No KEV entry was supplied.

Sources and references

Verified primary and authoritative sources

  • CVE-2023-1728 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2023-1728

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2023-1728 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2023-1728

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.