8.8
HIGH CVSS 3.1
CVE-2026-21853
AFFiNE: One-click Remote Code Execution through Custom URL Handling
Description

AFFiNE is an open-source, all-in-one workspace and an operating system. Prior to version 0.25.4, there is a one-click remote code execution vulnerability. This vulnerability can be exploited by embedding a specially crafted affine: URL on a website. An attacker can trigger the vulnerability in two common scenarios: 1/ A victim visits a malicious website controlled by the attacker and the website redirect to the URL automatically, or 2/ A victim clicks on a crafted link embedded on a legitimate website (e.g., in user-generated content). In both cases, the browser invokes AFFiNE custom URL handler, which launches the AFFiNE app and processes the crafted URL. This results in arbitrary code execution on the victim’s machine, without further interaction. This issue has been patched in version 0.25.4.

INFO

Published Date :

March 2, 2026, 7:16 p.m.

Last Modified :

March 2, 2026, 8:29 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-21853 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
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update AFFiNE to version 0.25.4 or later to fix the remote code execution vulnerability.
  • Update AFFiNE to version 0.25.4.
  • Apply patches for AFFiNE version 0.25.4.
  • Avoid clicking suspicious links.
  • Do not visit untrusted websites.
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-2026-21853.

URL Resource
https://github.com/toeverything/AFFiNE/commit/c9a4129a3e9376b688c18e1dcd6c87a775caac80
https://github.com/toeverything/AFFiNE/pull/13864
https://github.com/toeverything/AFFiNE/security/advisories/GHSA-67vm-2mcj-8965
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-21853 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-2026-21853 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-2026-21853 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-21853 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.

  • New CVE Received by [email protected]

    Mar. 02, 2026

    Action Type Old Value New Value
    Added Description AFFiNE is an open-source, all-in-one workspace and an operating system. Prior to version 0.25.4, there is a one-click remote code execution vulnerability. This vulnerability can be exploited by embedding a specially crafted affine: URL on a website. An attacker can trigger the vulnerability in two common scenarios: 1/ A victim visits a malicious website controlled by the attacker and the website redirect to the URL automatically, or 2/ A victim clicks on a crafted link embedded on a legitimate website (e.g., in user-generated content). In both cases, the browser invokes AFFiNE custom URL handler, which launches the AFFiNE app and processes the crafted URL. This results in arbitrary code execution on the victim’s machine, without further interaction. This issue has been patched in version 0.25.4.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
    Added CWE CWE-94
    Added Reference https://github.com/toeverything/AFFiNE/commit/c9a4129a3e9376b688c18e1dcd6c87a775caac80
    Added Reference https://github.com/toeverything/AFFiNE/pull/13864
    Added Reference https://github.com/toeverything/AFFiNE/security/advisories/GHSA-67vm-2mcj-8965
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 8.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact