CVE-2021-31924

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Summary

CVECVE-2021-31924
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-05-26 00:15:00 UTC
Updated2023-11-07 03:35:00 UTC
DescriptionYubico pam-u2f before 1.1.1 has a logic issue that, depending on the pam-u2f configuration and the application used, could lead to a local PIN bypass. This issue does not allow user presence (touch) or cryptographic signature verification to be bypassed, so an attacker would still need to physically possess and interact with the YubiKey or another enrolled authenticator. If pam-u2f is configured to require PIN authentication, and the application using pam-u2f allows the user to submit NULL as the PIN, pam-u2f will attempt to perform a FIDO2 authentication without PIN. If this authentication is successful, the PIN requirement is bypassed.

Risk And Classification

Problem Types: CWE-287

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Fedoraproject Fedora 34 All All All
Operating System Fedoraproject Fedora 35 All All All
Application Yubico Pam-u2f All All All All

References

ReferenceSourceLinkTags
[SECURITY] Fedora 34 Update: pam-u2f-1.2.0-2.fc34 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
[SECURITY] Fedora 34 Update: pam-u2f-1.2.0-2.fc34 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
pam-u2f MISC developers.yubico.com
Security Advisory YSA-2021-03 - Yubico MISC www.yubico.com
Yubico pam-u2f: Local PIN Bypass vulnerability (GLSA 202208-11) — Gentoo security GENTOO security.gentoo.org
[SECURITY] Fedora 35 Update: pam-u2f-1.2.0-2.fc35 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] Fedora 35 Update: pam-u2f-1.2.0-2.fc35 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 180555 Debian Security Update for pam-u2f (CVE-2021-31924)
  • 282106 Fedora Security Update for pam (FEDORA-2021-724f4733e9)
  • 282121 Fedora Security Update for pam (FEDORA-2021-a52d48b1c2)
  • 502148 Alpine Linux Security Update for pam-u2f
  • 710580 Gentoo Linux Yubico pam-u2f Local PIN Bypass Vulnerability (GLSA 202208-11)
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