CVE-2026-40947 json
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.
published 6mo ago modified 14d ago also EUVD-2026-23135
- cvss
- 2.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 2%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- Yubico libfido2 1.17.0
- Yubico python-fido2 2.2.0
- Yubico yubikey-manager 5.9.1
Is CVE-2026-40947 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6mo ago
Exploit prediction
0.13% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 2.9 | CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N |
Affected products
- Yubico libfido2
- Yubico python-fido2
- Yubico yubikey-manager
Classification
- Weakness
-
- CWE-426 Untrusted Search Path
References
Sources
- CVE List CVE-2026-40947
- NVD CVE-2026-40947
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.