CyberSecBulletin
CVE-2026-43998NVD status: Modified

vm2: Improper Link Resolution Before File Access

Published Updated By the CyberSecBulletin desk

CVE-2026-43998 is a high-severity improper link resolution before file access vulnerability in vm2 from Patriksimek, with a CVSS 3.1 base score of 8.5 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected vm2 versions: 3.10.5. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.72% chance of exploitation within 30 days, higher than 55% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of vm2 you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Patriksimekvm23.10.5Not stated
Red HatRed Hat Ansible Automation Platform 2.1Not specified in the recordNot stated
Red HatRed Hat Developer HubNot specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (github.com).

Scoring systemScoreSeverityScored by
CVSS 3.18.5HighCNA (github.com)
CVSS 3.18.5HighCNA

Official description

vm2 is an open source vm/sandbox for Node.js. In 3.10.5, NodeVM's require.root path restriction can be bypassed using filesystem symlinks, allowing sandboxed code to load modules from outside the allowed root directory in host context. Because path validation uses path.resolve() (which does not dereference symlinks) but module loading uses Node's native require() (which does), an attacker can load arbitrary host-realm modules and achieve remote code execution. This vulnerability is fixed in 3.11.0.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Link Resolution Before File Access

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

How developers prevent this class of flaw

  • Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

More Improper Link Resolution Before File Access vulnerabilities (CWE-59)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in vm2

All vm2 vulnerabilities

Recent Improper Link Resolution Before File Access vulnerabilities

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