Yubico libfido2/python-fido2/yubikey-manager untrusted search path

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in Yubico libfido2, python-fido2 and yubikey-manager. This impacts an unknown function. Executing a manipulation can lead to untrusted search path. This vulnerability is registered as CVE-2026-40947. The attack needs to be launched locally. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in Yubico libfido2, python-fido2 and yubikey-manager (the affected version unknown). This vulnerability affects an unknown part. The manipulation with an unknown input leads to a untrusted search path vulnerability. The CWE definition for the vulnerability is CWE-426. The product searches for critical resources using an externally-supplied search path that can point to resources that are not under the product's direct control. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Yubico libfido2 before 1.17.0, python-fido2 before 2.2.0, and yubikey-manager before 5.9.1 have an unintended DLL search path.

The advisory is available at yubico.com. This vulnerability was named CVE-2026-40947 since 04/16/2026. The exploitation appears to be difficult. Local access is required to approach this attack. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1574 by the MITRE ATT&CK project.

Upgrading eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.0
VulDB Meta Temp Score: 4.8

VulDB Base Score: 7.0
VulDB Temp Score: 6.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 2.9
CNA Vector (MITRE): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Untrusted search path
CWE: CWE-426
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

04/16/2026 Advisory disclosed
04/16/2026 +0 days CVE reserved
04/16/2026 +0 days VulDB entry created
04/16/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: yubico.com
Status: Confirmed

CVE: CVE-2026-40947 (🔒)
GCVE (CVE): GCVE-0-2026-40947
GCVE (VulDB): GCVE-100-357850

Entryinfo

Created: 04/16/2026 07:13
Changes: 04/16/2026 07:13 (62)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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