CVE-2026-25587: nyariv SandboxJS · Code Injection
Affects nyariv SandboxJSSource CVE Database V5
Not known to be exploited · CVSS 10.0 Critical : upgrade to 0.8.29 as a priority.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 53% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.8.29
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 6 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Upgrade SandboxJS and nyariv/SandboxJS to 0.8.29.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| nyarivSandboxJS | Affected
| Fixed in
|
GitHubnyariv/SandboxJSpkg:github/nyariv/SandboxJSOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
1. Immediate upgrade to SandboxJS version 0.8.29 or later, where the vulnerability is fixed. 2. Audit all applications and services using SandboxJS to identify vulnerable versions. 3. Implement strict Content Security Policies (CSP) to limit the execution of untrusted scripts and reduce attack surface. 4. Employ runtime application self-protection (RASP) tools that can detect and block sandbox escape attempts. 5. Review and harden sandbox configurations to exclude unsafe prototypes or methods from exposure. 6. Monitor logs and network traffic for unusual behavior indicative of sandbox escape or code injection attempts. 7. Educate developers on secure use of sandboxing libraries and the risks of prototype pollution. 8. Consider additional isolation layers such as containerization or virtual machines for executing untrusted code. 9. Engage in threat hunting exercises focused on detecting exploitation attempts targeting SandboxJS environments.
Description
SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, as Map is in SAFE_PROTOYPES, it's prototype can be obtained via Map.prototype. By overwriting Map.prototype.has the sandbox can be escaped. This vulnerability is fixed in 0.8.29.