CVE-2026-25641
SandboxJS has a sandbox escape via TOCTOU bug on keys in property accesses
Description
SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, there is a sandbox escape vulnerability due to a mismatch between the key on which the validation is performed and the key used for accessing properties. Even though the key used in property accesses is annotated as string, this is never enforced. So, attackers can pass malicious objects that coerce to different string values when used, e.g., one for the time the key is sanitized using hasOwnProperty(key) and a different one for when the key is used for the actual property access. This vulnerability is fixed in 0.8.29.
INFO
Published Date :
Feb. 6, 2026, 8:16 p.m.
Last Modified :
Feb. 6, 2026, 9:57 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-25641
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update SandboxJS to version 0.8.29 or later.
- Verify proper key validation and property access.
- Apply security patches from the vendor.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-25641.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-25641 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-25641
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-25641 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-25641 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Feb. 06, 2026
Action Type Old Value New Value Added Reference https://github.com/nyariv/SandboxJS/security/advisories/GHSA-7x3h-rm86-3342 -
New CVE Received by [email protected]
Feb. 06, 2026
Action Type Old Value New Value Added Description SandboxJS is a JavaScript sandboxing library. Prior to 0.8.29, there is a sandbox escape vulnerability due to a mismatch between the key on which the validation is performed and the key used for accessing properties. Even though the key used in property accesses is annotated as string, this is never enforced. So, attackers can pass malicious objects that coerce to different string values when used, e.g., one for the time the key is sanitized using hasOwnProperty(key) and a different one for when the key is used for the actual property access. This vulnerability is fixed in 0.8.29. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Added CWE CWE-367 Added Reference https://github.com/nyariv/SandboxJS/blob/6103d7147c4666fe48cfda58a4d5f37005b43754/src/executor.ts#L304-L304 Added Reference https://github.com/nyariv/SandboxJS/commit/67cb186c41c78c51464f70405504e8ef0a6e43c3 Added Reference https://github.com/nyariv/SandboxJS/security/advisories/GHSA-7x3h-rm86-3342