Summary
Electerm Security Vulnerability: RCE via malicious SSH server filename in openFileWithEditor
Fixed in version >= 3.7.9
Workarounds
Until a patch is available, it is strongly recommended to:
- Refrain from using the open with system editor or "Edit with custom editor" feature when connected to untrusted or unfamiliar SSH servers.
- Consider using the built-in editor for viewing files, as this path may not be vulnerable to the same injection.
- If the feature must be used, ensure connections are exclusively established with trusted servers and perform rigorous filename validation before editing.
Resources
Impact
A code execution (RCE) vulnerability exists in electerm's SFTP open with system editor or "Edit with custom editor" feature. When a user opts to edit a file using open with system editor or open with a custom editor, the filename is passed directly into a command line without sanitization.
A malicious actor controlling the SSH server or user OS can exploit this by crafting a filename containing shell metacharacters. If a victim subsequently attempts to edit this file, the injected commands are executed on their machine with the user's privileges. This could allow the attacker to run arbitrary code, install malware, or move laterally within the network.
Untrusted input reaches a shell command, allowing arbitrary commands to run on the host. Typical impact: code execution in the application's environment.
CVE-2026-43943 has a CVSS score of 8.8 (High). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (3.7.9); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2026-43943? CVE-2026-43943 is a high-severity OS command injection vulnerability in electerm (npm), affecting versions <= 3.7.8. It is fixed in 3.7.9. Untrusted input reaches a shell command, allowing arbitrary commands to run on the host.
- How severe is CVE-2026-43943? CVE-2026-43943 has a CVSS score of 8.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of electerm are affected by CVE-2026-43943? electerm (npm) versions <= 3.7.8 is affected.
- Is there a fix for CVE-2026-43943? Yes. CVE-2026-43943 is fixed in 3.7.9. Upgrade to this version or later.
- Is CVE-2026-43943 exploitable, and should I be worried? Whether CVE-2026-43943 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-43943 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-43943? Upgrade
electermto 3.7.9 or later.