CVE-2026-58266: CWE-346: Origin Validation Error in ankitects anki
Anki is a program for creating and reviewing flashcards. Prior to 25.09.4, Anki's webview-based pages communicate with the Rust backend using an internal localhost API, and user scripts included via iframes in the editor can access this API despite protections intended to block reviewer and editor scripts. A malicious imported card package with an embedded iframe can use exposed API methods such as getImageForOcclusion to read arbitrary files accessible to the Anki process and exfiltrate them over the network. This issue is fixed in version 25.09.4.
AI Analysis
Technical Summary
CVE-2026-58266 is an origin validation error (CWE-346) in ankitects Anki's webview communication with its Rust backend. Before version 25.09.4, user scripts included via iframes in the editor can access internal localhost API methods, such as getImageForOcclusion, despite protections meant to block such access. This allows a malicious imported card package to read arbitrary files accessible to the Anki process and exfiltrate them over the network. The issue is resolved in Anki version 25.09.4.
Potential Impact
An attacker who imports a malicious card package with an embedded iframe can exploit this vulnerability to read arbitrary files accessible by the Anki process and exfiltrate their contents over the network. This compromises confidentiality of local data accessible to Anki. There is no indication of integrity or availability impact. The CVSS 3.1 base score is 6.5 (medium severity), reflecting network attack vector, low attack complexity, no privileges required, user interaction required, unchanged scope, high confidentiality impact, and no integrity or availability impact.
Mitigation Recommendations
This vulnerability is fixed in Anki version 25.09.4. Users should upgrade to version 25.09.4 or later to remediate this issue. No other official remediation or temporary fixes are documented. Since this is not a cloud service, remediation depends on user upgrade.
CVE-2026-58266: CWE-346: Origin Validation Error in ankitects anki
Description
Anki is a program for creating and reviewing flashcards. Prior to 25.09.4, Anki's webview-based pages communicate with the Rust backend using an internal localhost API, and user scripts included via iframes in the editor can access this API despite protections intended to block reviewer and editor scripts. A malicious imported card package with an embedded iframe can use exposed API methods such as getImageForOcclusion to read arbitrary files accessible to the Anki process and exfiltrate them over the network. This issue is fixed in version 25.09.4.
CVSS v3.1
Score 6.5medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-58266 is an origin validation error (CWE-346) in ankitects Anki's webview communication with its Rust backend. Before version 25.09.4, user scripts included via iframes in the editor can access internal localhost API methods, such as getImageForOcclusion, despite protections meant to block such access. This allows a malicious imported card package to read arbitrary files accessible to the Anki process and exfiltrate them over the network. The issue is resolved in Anki version 25.09.4.
Potential Impact
An attacker who imports a malicious card package with an embedded iframe can exploit this vulnerability to read arbitrary files accessible by the Anki process and exfiltrate their contents over the network. This compromises confidentiality of local data accessible to Anki. There is no indication of integrity or availability impact. The CVSS 3.1 base score is 6.5 (medium severity), reflecting network attack vector, low attack complexity, no privileges required, user interaction required, unchanged scope, high confidentiality impact, and no integrity or availability impact.
Mitigation Recommendations
This vulnerability is fixed in Anki version 25.09.4. Users should upgrade to version 25.09.4 or later to remediate this issue. No other official remediation or temporary fixes are documented. Since this is not a cloud service, remediation depends on user upgrade.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-29T21:54:30.331Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a4d7350c9d9e3dbe3e36b3d
Added to database: 07/07/2026, 21:44:48 UTC
Last enriched: 07/15/2026, 12:14:41 UTC
Last updated: 08/20/2026, 10:52:10 UTC
Views: 100
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