vm2: Insecure Default Variable Initialization
CVE-2026-92950 is a high-severity insecure default variable initialization vulnerability in vm2 from Patriksimek, with a CVSS 3.1 base score of 8.6 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 3.11.7 as the first without the flaw, so updating vm2 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.2% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update vm2 to 3.11.7 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Patriksimek | vm2 | before 3.11.7 | 3.11.7 |
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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- 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:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 9.3 | Critical | CNA (vulncheck.com) |
| CVSS 3.1 | 8.6 | High | CNA (vulncheck.com) |
Official description
vm2 before 3.11.7 contains a sandbox escape vulnerability in the CLI tool that allows attackers to execute arbitrary code in the host Node.js process. Attackers can supply a malicious script file to the vm2 CLI that uses require(__filename) to re-execute itself in the host realm, bypassing sandbox isolation and accessing host modules like fs and child_process.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Insecure Default Variable Initialization
The product, by default, initializes an internal variable with an insecure or less secure value than is possible.
How developers prevent this class of flaw
- Disable or change default settings when they can be used to abuse the system. Since those default settings are shipped with the product they are likely to be known by a potential attacker who is familiar with the product. For instance, default credentials should be changed or the associated accounts should be disabled.
More Insecure Default Variable Initialization vulnerabilities (CWE-453)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
References
Other vulnerabilities in vm2
- 7.5 High severity
- 9.0 Critical severity
- 10.0 Critical severity
- 10.0 Critical severity
- 7.2 High severity
- 10.0 Critical severity
Recent Insecure Default Variable Initialization vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.5 High severity
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