Improper input validation in yubico-pam
Priority MEDIUM 46CWE-20Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
Yubico PAM Module before 2.10 performed user authentication when 'use_first_pass' PAM configuration option was not used and the module was configured as 'sufficient' in the PAM configuration. A remote attacker could use this flaw to circumvent common authentication process and obtain access to the account in question by providing a NULL value (pressing Ctrl-D keyboard sequence) as the password string.
Why it matters now
EPSS 0.02019 81st percentileScored 2026-11-07
Fix Fixed yubico-pam (yubico-pam): 2.10
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| yubico-pam | yubico-pam | before 2.10 | 2.10 | Patch available | CNA |
- yubico-pam Vendoryubico-pam Affected before 2.10 Fixed in 2.10 Patch available CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:yubico:pam_module:*:*:*:*:*:*:*:* | before 2.10 | Vulnerable | Yubico |
| cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Linux |
| cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* | 8.0 | Vulnerable | Debian |
| cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Debian |
| cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* | 10.0 | Vulnerable | Debian |
- cpe:2.3:a:yubico:pam_module:*:*:*:*:*:*:*:* Versions before 2.10 Vulnerable ·Yubico
- cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Linux
- cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Debian
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
Remediation
- Fix · CNA yubico-pam (yubico-pam) Fixed in 2.10
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2011-4120
- 2026-10-03 Alias added: GHSA-4qc6-w2f8-x2pc
References
Sources
- CVE-2011-4120 · CVE Program
- CVE-2011-4120 · NVD
- FIRST EPSS
- GHSA-4qc6-w2f8-x2pc · GitHub Advisory Database · CC BY 4.0
- CVE-2011-4120 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences