CVE-2026-21853 (GCVE-0-2026-21853)
Vulnerability from cvelistv5 – Published: 2026-03-02 18:55 – Updated: 2026-03-02 19:19
VLAI
EPSS
VEX
Title
AFFiNE: One-click Remote Code Execution through Custom URL Handling
Summary
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.
Severity
8.8 (High)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-02 19:18 UTC
CWE
- CWE-94 - Improper Control of Generation of Code ('Code Injection')
Assigner
GitHub_M
CNA
References
3 references
| URL | Tags |
|---|---|
| https://github.com/toeverything/AFFiNE/security/a… | x_refsource_CONFIRM |
| https://github.com/toeverything/AFFiNE/pull/13864 | x_refsource_MISC |
| https://github.com/toeverything/AFFiNE/commit/c9a… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| toeverything | AFFiNE |
Affected:
< 0.25.4
|
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Nomenclature
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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