nyariv SandboxJS up to 0.8.28 hosts Object.values/Object.entries injection

Summaryinfo

A vulnerability, which was classified as problematic, has been found in nyariv SandboxJS up to 0.8.28. This affects the function hosts. This manipulation of the argument Object.values/Object.entries causes injection. This vulnerability is tracked as CVE-2026-25520. The attack is possible to be carried out remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in nyariv SandboxJS up to 0.8.28. Affected by this vulnerability is the function hosts. The manipulation of the argument Object.values/Object.entries with an unknown input leads to a injection vulnerability. The CWE definition for the vulnerability is CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, The return values of functions aren't wrapped. Object.values/Object.entries can be used to get an Array containing the host's Function constructor, by using Array.prototype.at you can obtain the hosts Function constructor, which can be used to execute arbitrary code outside of the sandbox. This vulnerability is fixed in 0.8.29.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-25520 since 02/02/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1055 for this issue.

Upgrading to version 0.8.29 eliminates this vulnerability. Applying the patch 67cb186c41c78c51464f70405504e8ef0a6e43c3 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-5591). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• nyariv

Name

• SandboxJS

Version

• 0.8.0
• 0.8.1
• 0.8.2
• 0.8.3
• 0.8.4
• 0.8.5
• 0.8.6
• 0.8.7
• 0.8.8
• 0.8.9
• 0.8.10
• 0.8.11
• 0.8.12
• 0.8.13
• 0.8.14
• 0.8.15
• 0.8.16
• 0.8.17
• 0.8.18
• 0.8.19
• 0.8.20
• 0.8.21
• 0.8.22
• 0.8.23
• 0.8.24
• 0.8.25
• 0.8.26
• 0.8.27
• 0.8.28

License

• open-source

Website

• Product: https://github.com/nyariv/SandboxJS/

CPE 2.3info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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