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TI-2020-16865 Aliases CVE-2020-27780GHSA-pgjg-jx8c-q35f

Improper authentication in pam

Priority MEDIUM 46CWE-287Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-287.

Summary

A flaw was found in Linux-Pam in versions prior to 1.5.1 in the way it handle empty passwords for non-existing users. When the user doesn't exist PAM try to authenticate with root and in the case of an empty password it successfully authenticate.

Why it matters now

EPSS 0.01959 80th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—pampam 1.5.1—No fix listedCNA
  • pam Vendor— Affected pam 1.5.1 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:linux-pam:linux-pam:*:*:*:*:*:*:*:*1.5.0 to before 1.5.1VulnerableLinux-PAM
  • cpe:2.3:a:linux-pam:linux-pam:*:*:*:*:*:*:*:* Versions 1.5.0 to before 1.5.1 Vulnerable ·Linux-PAM

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Not affected: 4 products
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-27780
  2. 2026-10-03 Alias added: GHSA-pgjg-jx8c-q35f

References

Advisory 1

  • TI-2022-11097 The Linux-PAM package before 1.5.2-6.1 for openSUSE Tumbleweed allows authentication… CVSS 3.1CRITICAL 9.8
  • TI-2015-02867 The _unix_run_helper_binary function in the pam_unix module in Linux-PAM (aka pam) before… CVSS 3.0MEDIUM 6.5
  • TI-2014-02069 Multiple directory traversal vulnerabilities in pam_timestamp.c in the pam_timestamp… CVSS 2.0MEDIUM 5.8
  • TI-2009-00845 Integer signedness error in the _pam_StrTok function in libpam/pam_misc.c in Linux-PAM… CVSS 2.0MEDIUM 6.6
  • TI-2010-04431 The pam_env module in Linux-PAM (aka pam) 1.1.2 and earlier reads the .pam_environment… CVSS 2.0HIGH 7.2
  • TI-2010-03660 pam_namespace.c in the pam_namespace module in Linux-PAM (aka pam) before 1.1.3 uses the… CVSS 2.0MEDIUM 6.9
See all 17 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences