CVE-2025-61785
Deno's --deny-write check does not prevent permission bypass
Description
Deno is a JavaScript, TypeScript, and WebAssembly runtime. In versions prior to 2.5.3 and 2.2.15, `Deno.FsFile.prototype.utime` and `Deno.FsFile.prototype.utimeSync` are not limited by the permission model check `--deny-write=./`. It's possible to change to change the access (`atime`) and modification (`mtime`) times on the file stream resource even when the file is opened with `read` only permission (and `write`: `false`) and file write operations are not allowed (the script is executed with `--deny-write=./`). Similar APIs like `Deno.utime` and `Deno.utimeSync` require `allow-write` permission, however, when a file is opened, even with read only flags and deny-write permission, it's still possible to change the access (`atime`) and modification (`mtime`) times, and thus bypass the permission model. Versions 2.5.3 and 2.2.15 fix the issue.
INFO
Published Date :
Oct. 8, 2025, 1:15 a.m.
Last Modified :
Oct. 16, 2025, 6:12 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.0 | LOW | [email protected] | ||||
| CVSS 3.1 | LOW | [email protected] |
Solution
- Update Deno to version 2.5.3 or later.
- Update Deno to version 2.2.15 or later.
- Ensure file write permissions are correctly configured.
Public PoC/Exploit Available at Github
CVE-2025-61785 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
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-2025-61785.
| URL | Resource |
|---|---|
| https://github.com/denoland/deno/commit/992e998dfe436cdc9325232759af8be92f11739b | Patch |
| https://github.com/denoland/deno/pull/30872 | Issue Tracking Patch |
| https://github.com/denoland/deno/releases/tag/v2.2.15 | Release Notes |
| https://github.com/denoland/deno/releases/tag/v2.5.3 | Release Notes |
| https://github.com/denoland/deno/security/advisories/GHSA-vg2r-rmgp-cgqj | Exploit Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-61785 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-2025-61785
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).
My personal repository
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-61785 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-61785 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.
-
Initial Analysis by [email protected]
Oct. 16, 2025
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N Added CPE Configuration OR *cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:* versions up to (including) 2.2.15 *cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:* versions from (including) 2.3.0 up to (excluding) 2.5.3 Added Reference Type GitHub, Inc.: https://github.com/denoland/deno/commit/992e998dfe436cdc9325232759af8be92f11739b Types: Patch Added Reference Type GitHub, Inc.: https://github.com/denoland/deno/pull/30872 Types: Issue Tracking, Patch Added Reference Type GitHub, Inc.: https://github.com/denoland/deno/releases/tag/v2.2.15 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/denoland/deno/releases/tag/v2.5.3 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/denoland/deno/security/advisories/GHSA-vg2r-rmgp-cgqj Types: Exploit, Vendor Advisory -
New CVE Received by [email protected]
Oct. 08, 2025
Action Type Old Value New Value Added Description Deno is a JavaScript, TypeScript, and WebAssembly runtime. In versions prior to 2.5.3 and 2.2.15, `Deno.FsFile.prototype.utime` and `Deno.FsFile.prototype.utimeSync` are not limited by the permission model check `--deny-write=./`. It's possible to change to change the access (`atime`) and modification (`mtime`) times on the file stream resource even when the file is opened with `read` only permission (and `write`: `false`) and file write operations are not allowed (the script is executed with `--deny-write=./`). Similar APIs like `Deno.utime` and `Deno.utimeSync` require `allow-write` permission, however, when a file is opened, even with read only flags and deny-write permission, it's still possible to change the access (`atime`) and modification (`mtime`) times, and thus bypass the permission model. Versions 2.5.3 and 2.2.15 fix the issue. Added CVSS V3 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N Added CWE CWE-266 Added Reference https://github.com/denoland/deno/commit/992e998dfe436cdc9325232759af8be92f11739b Added Reference https://github.com/denoland/deno/pull/30872 Added Reference https://github.com/denoland/deno/releases/tag/v2.2.15 Added Reference https://github.com/denoland/deno/releases/tag/v2.5.3 Added Reference https://github.com/denoland/deno/security/advisories/GHSA-vg2r-rmgp-cgqj