Electerm has an unvalidated shell.openExternal that allows arbitrary protocol execution via terminal link click

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.8 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS

• CVE-2026-43941: 0.39% estimated exploitation activity in the next 30 days; percentile 33.65 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact Electerm's terminal hyperlink handler passes any URL clicked in the terminal directly to shell.openExternal without any protocol validation. When a user connects to a malicious SSH server, the attacker can print a crafted URI in the terminal output. If the victim clicks the link, shell.openExternal executes it using the operating system's default protocol handler. This can be abused to: - Trigger dangerous protocol handlers (ms-msdt:, search-ms:) for code execution - Open local files or network shares (file://, UNC paths) to leak NTLM hashes or exfiltrate data - Launch any installed application associated with a custom URI scheme An attacker who controls terminal output (e.g., via a malicious SSH server, compromised remote host, or malicious plugin rendering terminal content) can thus achieve arbitrary code execution or local file access on the victim's machine, requiring only that the victim clicks a displayed link. Patches As of electerm v3.7.9, no official patch has been…

Published by the source

8 May 2026, 18:35 UTC

Last modified by the source

8 May 2026, 18:56 UTC

Source last checked

26 Oct 2026, 12:51 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-fwf6-j56g-m97c

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-fwf6-j56g-m97c

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-43941

Advisory: Electerm has an unvalidated shell.openExternal that allows arbitrary protocol execution via terminal link click
IDs: CVE-2026-43941, GHSA-fwf6-j56g-m97c
Record: https://patchnext.com/advisories/cve-2026-43941 (revision 2, source checked 26 Oct 2026, 12:51 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm electerm: affected <= 3.8.15

## Suggested inspection (read-only)
- `npm ls electerm --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on electerm.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-fwf6-j56g-m97c (OSV record GHSA-fwf6-j56g-m97c lists affected ranges: npm electerm >=0 <=3.8.15)
- Verified: https://github.com/advisories/GHSA-fwf6-j56g-m97c (GitHub-reviewed advisory GHSA-fwf6-j56g-m97c lists affected ranges: npm electerm >=0 <=3.8.15)

Commands are suggestions: review each one before running it.