electerm: Path traversal in electerm runWidget leads to arbitrary code execution

published 2026-05-08 6 mo ago modified 2026-06-17 4 mo ago also GHSA-f77v-9vpc-6pjm , EUVD-2026-28512

cvss: 8.4; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits: 0; none known

electerm is an open-sourced terminal/ssh/sftp/telnet/serialport/RDP/VNC/Spice/ftp client. Prior to version 3.7.16, the runWidget function in src/app/widgets/load-widget.js constructs a file path by directly concatenating user‑supplied widget identifiers without any sanitisation. Because runWidget is exposed to the renderer process via an asynchronous IPC handler with no input validation, an attacker who achieves JavaScript execution inside the renderer (for example, through a malicious plugin or a cross‑site scripting flaw in the built‑in webview) can abuse a path traversal (../) to load and execute an arbitrary JavaScript file anywhere on the victim’s filesystem. This gives the attacker local code execution with the full privileges of the electerm process, leading to complete system compromise. This issue has been patched in version 3.7.16.

Patch / fix

fixed in 2 links 1

npm electerm 3.7.16
electerm_project electerm 3.7.16

github.com/electerm/electerm/releases/tag/v3.7.16 release

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 6 mo ago (2026-05-08)

Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.4	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
GitHub	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected packages

ecosystem	package	affected	fixed in
npm	electerm	<3.7.16	3.7.16

Affected products

electerm electerm

Classification

Weakness

CWE-22 Improper Limitation of a Pathname to a Restricted Directory
CWE-829 Inclusion of Functionality from Untrusted Control Sphere

References

github.com /electerm/electerm/security/advisories/GHSA-f77v-9vpc-6pjm
web, mitigation, vendor-advisory
github.com /electerm/electerm/releases/tag/v3.7.16
web, release-notes
nvd.nist.gov /vuln/detail/CVE-2026-43940
advisory
github.com /electerm/electerm
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary