CVE-2020-27780

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Source
https://cve.org/CVERecord?id=CVE-2020-27780
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-27780.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2020-27780
Downstream
Related
Published
2020-12-18T00:15:14Z
Modified
2026-08-07T15:12:38Z
Severity
  • 9.8 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
[none]
Details

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.

References

Affected packages

Git / github.com/linux-pam/linux-pam

Affected ranges

Type
GIT
Repo
https://github.com/linux-pam/linux-pam
Events
Introduced
62d826471e87e27b39a36ccbeee58999e2514a92
Fixed
225f17470eed9f44282f435ad1ed64c94d9a2ddf
Database specific
Show details 
{
    "cpe":  "cpe:2.3:a:linux-pam:linux-pam:*:*:*:*:*:*:*:*",
    "extracted_events":  [
        {
            "introduced":  "1.5.0"
        },
        {
            "fixed":  "1.5.1"
        }
    ],
    "source":  "CPE_RANGE"
}

Affected versions

v1.*
v1.5.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-27780.json"
vanir_signatures 
[
    {
        "deprecated":  false,
        "digest":  {
            "line_hashes":  [
                "236274917370666437465787812312716913764",
                "191165804437170388625080527033927485485",
                "248212176959400049713618959841331975794",
                "74187730262540881415256141112760525222",
                "53241490001132424225404146543772968193",
                "169694962436386515826333909717745520461",
                "339114646913897635961686157876483083914",
                "200902990943821488650428420571812193360"
            ],
            "threshold":  0.9
        },
        "id":  "CVE-2020-27780-90a0a465",
        "signature_type":  "Line",
        "signature_version":  "v1",
        "source":  "https://github.com/linux-pam/linux-pam/commit/225f17470eed9f44282f435ad1ed64c94d9a2ddf",
        "target":  {
            "file":  "modules/pam_unix/bigcrypt.c"
        }
    },
    {
        "deprecated":  false,
        "digest":  {
            "function_hash":  "251657082591479008743931529537448873642",
            "length":  1660
        },
        "id":  "CVE-2020-27780-febf053a",
        "signature_type":  "Function",
        "signature_version":  "v1",
        "source":  "https://github.com/linux-pam/linux-pam/commit/225f17470eed9f44282f435ad1ed64c94d9a2ddf",
        "target":  {
            "file":  "modules/pam_unix/bigcrypt.c",
            "function":  "bigcrypt"
        }
    }
]
vanir_signatures_modified 
"2026-08-07T15:12:38Z"