Skip to content

GHSA-rjf2-j2r6-q8gr CVE-2021-23449 SNYK-JS-VM2-1585918

Prototype Pollution in vm2

Critical npm
Severity
9.8 / 10
Critical · CVSS 3.1
Exploit chance (EPSS)
3.59%
Chance of exploitation in the next 30 days. Higher than 89.43% of scored vulnerabilities.
Known exploited
No
Not in CISA's catalog
Weakness
CWE-1321 Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
CWE-915 Improperly Controlled Modification of Dynamically-Determined Object Attributes
Fix
3.9.4
Upgrade vm2 to this version or later

Description

This affects the package vm2 before 3.9.4. Prototype Pollution attack vector can lead to sandbox escape and execution of arbitrary code on the host machine.

Affected versions

npm

PackageVulnerableFixed in
vm2
< 3.9.4
3.9.4

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

vm2 npm → 3.9.4

npm
npm install vm2@3.9.4
yarn
yarn add vm2@3.9.4
pnpm
pnpm add vm2@3.9.4

Severity breakdown

CVSS 3.1 9.8

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

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Weakness

CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.

How to prevent it
  • Implementation: By freezing the object prototype first (for example, Object.freeze(Object.prototype)), modification of the prototype becomes impossible.
  • Architecture and Design: By blocking modifications of attributes that resolve to object prototype, such as proto or prototype, this weakness can be mitigated.
  • Implementation: When handling untrusted objects, validating using a schema can be used.
  • Implementation: By using an object without prototypes (via Object.create(null) ), adding object prototype attributes by accessing the prototype via the special attributes becomes impossible, mitigating this weakness.
  • Implementation: Map can be used instead of objects in most cases. If Map methods are used instead of object attributes, it is not possible to access the object prototype or modify it.

CWE-915: Improperly Controlled Modification of Dynamically-Determined Object Attributes

The product receives input from an upstream component that specifies multiple attributes, properties, or fields that are to be initialized or updated in an object, but it does not properly control which attributes can be modified.

How to prevent it
  • Implementation: If available, use features of the language or framework that allow specification of allowlists of attributes or fields that are allowed to be modified. If possible, prefer allowlists over denylists. For applications written with Ruby on Rails, use the attr_accessible (allowlist) or attr_protected (denylist) macros in each class that may be used in mass assignment.
  • Architecture and Design, Implementation: If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • Implementation: For any externally-influenced input, check the input against an allowlist of internal object attributes or fields that are allowed to be modified.
  • Implementation, Architecture and Design: Refactor the code so that object attributes or fields do not need to be dynamically identified, and only expose getter/setter functionality for the intended attributes.

References

Timeline

  1. Published
  2. Last updated by the source
  3. Latest EPSS score
AdvisorySeverityWhy it's related
GHSA-489w-w794-jq94
vm2: NodeVM zlib Buffers expose pooled host memory across the VM boundary
High Also affects vm2
GHSA-2v2p-6j97-cjg9
vm2: Host Promise rejection from an exposed constructor can terminate the vm2 host process
Medium Also affects vm2
GHSA-5h3f-q97h-ccvc
vm2: NodeVM custom resolution bypasses external path boundaries
Critical Also affects vm2
GHSA-pq68-rvw4-xp4r
vm2 contains a sandbox escape vulnerability
Critical Also affects vm2
GHSA-f8gf-w286-fmq2
vm2: `allowAsync: false` can be bypassed through Promise thenable assimilation in VM and NodeVM
High Also affects vm2
GHSA-6rh5-qq4q-97xh
vm2: NodeVM builtin denylist bypass via fs/promises despite -fs, allowing host filesystem writes
High Also affects vm2
GHSA-8686-vhfx-7r3j
vm2: NodeVM node:-prefixed negative builtin deny bypass exposes child_process
Critical Also affects vm2
GHSA-wjwh-qqvp-g4p4
vm2 sandbox escape via WebAssembly.compileStreaming Promise species bypass
Critical Also affects vm2
Is this in your code?

MergeHarbor checks every repository's dependencies against this database, ranks what matters by exploitability and reachability, routes it to the owning team and opens the fix pull request.

Check your repos with MergeHarbor