CVE-2026-40947: CWE-426 Untrusted Search Path in Yubico libfido2
CVE-2026-40947 is a low-severity vulnerability in Yubico's libfido2, python-fido2, and yubikey-manager products prior to versions 1. 17. 0, 2. 2. 0, and 5. 9. 1 respectively. The issue involves an unintended DLL search path (CWE-426), which could lead to the loading of untrusted DLLs. The vulnerability has a CVSS score of 2. 9, indicating low impact, with no confidentiality or availability impact and only limited integrity impact.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-40947) affects Yubico's libfido2 library and related products by having an unintended DLL search path, categorized under CWE-426 (Untrusted Search Path). This means that when these products load DLLs, they may do so from directories that are not secure or intended, potentially allowing an attacker with local access to influence which DLL is loaded. The CVSS 3.1 vector indicates the attack requires local access with high attack complexity and no privileges or user interaction, resulting in limited integrity impact only. The affected versions are prior to libfido2 1.17.0, python-fido2 2.2.0, and yubikey-manager 5.9.1. No official remediation level or patch links are currently provided.
Potential Impact
The impact is limited to potential integrity issues due to the unintended DLL search path. There is no impact on confidentiality or availability. Exploitation requires local access and is considered complex. No known exploits have been reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict local access to trusted users and environments to reduce risk. Monitor for vendor updates regarding patches or official mitigations.
CVE-2026-40947: CWE-426 Untrusted Search Path in Yubico libfido2
Description
CVE-2026-40947 is a low-severity vulnerability in Yubico's libfido2, python-fido2, and yubikey-manager products prior to versions 1. 17. 0, 2. 2. 0, and 5. 9. 1 respectively. The issue involves an unintended DLL search path (CWE-426), which could lead to the loading of untrusted DLLs. The vulnerability has a CVSS score of 2. 9, indicating low impact, with no confidentiality or availability impact and only limited integrity impact.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-40947) affects Yubico's libfido2 library and related products by having an unintended DLL search path, categorized under CWE-426 (Untrusted Search Path). This means that when these products load DLLs, they may do so from directories that are not secure or intended, potentially allowing an attacker with local access to influence which DLL is loaded. The CVSS 3.1 vector indicates the attack requires local access with high attack complexity and no privileges or user interaction, resulting in limited integrity impact only. The affected versions are prior to libfido2 1.17.0, python-fido2 2.2.0, and yubikey-manager 5.9.1. No official remediation level or patch links are currently provided.
Potential Impact
The impact is limited to potential integrity issues due to the unintended DLL search path. There is no impact on confidentiality or availability. Exploitation requires local access and is considered complex. No known exploits have been reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict local access to trusted users and environments to reduce risk. Monitor for vendor updates regarding patches or official mitigations.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-04-15T23:11:52.721Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e01ffb82d89c981fa83035
Added to database: 4/15/2026, 11:32:11 PM
Last enriched: 4/15/2026, 11:46:56 PM
Last updated: 4/16/2026, 1:01:30 AM
Views: 6
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