Vulnerability-Lookup

ubuntu-cve-2026-54411

Vulnerability from osv_ubuntu

Published

2026-06-14 18:17

Modified

2026-08-13 00:10

Summary

Details

Linux-PAM through 1.7.2 contains an observable timing discrepancy (CWE-208) in the pam_userdb module's plaintext-password comparison path in modules/pam_userdb/pam_userdb.c that allows a local or network-adjacent attacker able to repeatedly drive authentication through a calling service to recover the plaintext password of a target account by measuring response-timing differences.

Severity

5.9 (Medium)


                    
                      CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

6.9 (Medium)


                    
                      CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/AU:N/V:D

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-54411	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-54411	REPORT
	https://ubuntu.com/security/notices/USN-8601-1	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libpam-cracklib",
            "binary_version": "1.1.8-1ubuntu2.2+esm4"
          },
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.1.8-1ubuntu2.2+esm4"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.1.8-1ubuntu2.2+esm4"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.1.8-1ubuntu2.2+esm4"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.1.8-1ubuntu2.2+esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.1.8-1ubuntu2.2+esm4?arch=source\u0026distro=esm-infra-legacy/trusty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.1.3-8ubuntu3",
        "1.1.3-10ubuntu1",
        "1.1.3-11ubuntu1",
        "1.1.8-1ubuntu1",
        "1.1.8-1ubuntu2",
        "1.1.8-1ubuntu2.1",
        "1.1.8-1ubuntu2.2",
        "1.1.8-1ubuntu2.2+esm1",
        "1.1.8-1ubuntu2.2+esm3",
        "1.1.8-1ubuntu2.2+esm4"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libpam-cracklib",
            "binary_version": "1.1.8-3.2ubuntu2.3+esm5"
          },
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.1.8-3.2ubuntu2.3+esm5"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.1.8-3.2ubuntu2.3+esm5"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.1.8-3.2ubuntu2.3+esm5"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.1.8-3.2ubuntu2.3+esm5"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.1.8-3.2ubuntu2.3+esm5?arch=source\u0026distro=esm-infra/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.1.8-3.1ubuntu3",
        "1.1.8-3.2ubuntu2",
        "1.1.8-3.2ubuntu2.1",
        "1.1.8-3.2ubuntu2.3",
        "1.1.8-3.2ubuntu2.3+esm1",
        "1.1.8-3.2ubuntu2.3+esm2",
        "1.1.8-3.2ubuntu2.3+esm4",
        "1.1.8-3.2ubuntu2.3+esm5"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libpam-cracklib",
            "binary_version": "1.1.8-3.6ubuntu2.18.04.6+esm1"
          },
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.1.8-3.6ubuntu2.18.04.6+esm1"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.1.8-3.6ubuntu2.18.04.6+esm1"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.1.8-3.6ubuntu2.18.04.6+esm1"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.1.8-3.6ubuntu2.18.04.6+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.1.8-3.6ubuntu2.18.04.6+esm1?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.1.8-3.2ubuntu3",
        "1.1.8-3.2ubuntu4",
        "1.1.8-3.6ubuntu1",
        "1.1.8-3.6ubuntu2",
        "1.1.8-3.6ubuntu2.18.04.1",
        "1.1.8-3.6ubuntu2.18.04.2",
        "1.1.8-3.6ubuntu2.18.04.3",
        "1.1.8-3.6ubuntu2.18.04.4",
        "1.1.8-3.6ubuntu2.18.04.6",
        "1.1.8-3.6ubuntu2.18.04.6+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libpam-cracklib",
            "binary_version": "1.3.1-5ubuntu4.7"
          },
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.3.1-5ubuntu4.7"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.3.1-5ubuntu4.7"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.3.1-5ubuntu4.7"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.3.1-5ubuntu4.7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.3.1-5ubuntu4.7?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.1-5ubuntu1",
        "1.3.1-5ubuntu3",
        "1.3.1-5ubuntu4",
        "1.3.1-5ubuntu4.1",
        "1.3.1-5ubuntu4.2",
        "1.3.1-5ubuntu4.3",
        "1.3.1-5ubuntu4.4",
        "1.3.1-5ubuntu4.6",
        "1.3.1-5ubuntu4.7"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libpam-cracklib",
            "binary_version": "1.4.0-11ubuntu2.7"
          },
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.4.0-11ubuntu2.7"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.4.0-11ubuntu2.7"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.4.0-11ubuntu2.7"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.4.0-11ubuntu2.7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.4.0-11ubuntu2.7?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.4.0-11ubuntu2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.1-5ubuntu11",
        "1.4.0-10ubuntu1",
        "1.4.0-10ubuntu2",
        "1.4.0-11ubuntu1",
        "1.4.0-11ubuntu2",
        "1.4.0-11ubuntu2.1",
        "1.4.0-11ubuntu2.3",
        "1.4.0-11ubuntu2.4",
        "1.4.0-11ubuntu2.5",
        "1.4.0-11ubuntu2.6"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.5.3-5ubuntu5.6"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.5.3-5ubuntu5.6"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.5.3-5ubuntu5.6"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.5.3-5ubuntu5.6"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.5.3-5ubuntu5.6?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.5.3-5ubuntu5.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.5.2-6ubuntu1",
        "1.5.2-9.1ubuntu1",
        "1.5.2-9.1ubuntu2",
        "1.5.2-9.1ubuntu3",
        "1.5.3-5ubuntu3",
        "1.5.3-5ubuntu4",
        "1.5.3-5ubuntu5",
        "1.5.3-5ubuntu5.1",
        "1.5.3-5ubuntu5.4",
        "1.5.3-5ubuntu5.5"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.7.0-5ubuntu2"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.7.0-5ubuntu2"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.7.0-5ubuntu2"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.7.0-5ubuntu2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.7.0-5ubuntu2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.5.3-7ubuntu4",
        "1.5.3-7ubuntu5",
        "1.5.3-7ubuntu6",
        "1.7.0-5ubuntu1",
        "1.7.0-5ubuntu2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.7.0-5ubuntu3.1"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.7.0-5ubuntu3.1"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.7.0-5ubuntu3.1"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.7.0-5ubuntu3.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.7.0-5ubuntu3.1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.7.0-5ubuntu3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.7.0-5ubuntu2",
        "1.7.0-5ubuntu3"
      ]
    }
  ],
  "aliases": [],
  "details": "Linux-PAM through 1.7.2 contains an observable timing discrepancy (CWE-208) in the pam_userdb module\u0027s plaintext-password comparison path in modules/pam_userdb/pam_userdb.c that allows a local or network-adjacent attacker able to repeatedly drive authentication through a calling service to recover the plaintext password of a target account by measuring response-timing differences.",
  "id": "UBUNTU-CVE-2026-54411",
  "modified": "2026-08-13T00:10:32Z",
  "published": "2026-06-14T18:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-54411"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-54411"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8601-1"
    }
  ],
  "related": [
    "USN-8601-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/AU:N/V:D",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-54411"
  ]
}

CVE-2026-54411 (GCVE-0-2026-54411)

Vulnerability from cvelistv5 – Published: 2026-06-14 17:21 – Updated: 2026-08-10 11:43

Title

Linux-PAM pam_userdb Observable Timing Discrepancy in Plaintext Password Comparison

Summary

Severity

6.9 (Medium)


                        
                          CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/AU:N/V:D

5.9 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-15 16:59 UTC

CWE

CWE-208 - Observable Timing Discrepancy

Assigner

TuranSec redhat root

References

4 references

URL	Tags
https://github.com/linux-pam/linux-pam	product
https://github.com/linux-pam/linux-pam/blob/maste…	product
https://github.com/linux-pam/linux-pam/blob/maste…	product
https://cwe.mitre.org/data/definitions/208.html	technical-description

Impacted products

1 product

Vendor	Product	Version
Linux-PAM	Linux-PAM	Affected: 0 , ≤ 1.7.2 (semver)

Date Public

2026-06-14 17:21

Credits

Xurshidbek Sobirjonov

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-54411",
                "options": [
                  {
                    "Exploitation": "none"
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                    "Technical Impact": "partial"
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                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-15T16:59:25.401303Z",
                "version": "2.0.3"
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        ],
        "providerMetadata": {
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
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        "title": "CISA ADP Vulnrichment"
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    ],
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              "version": "0",
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            }
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      "credits": [
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          "lang": "en",
          "type": "finder",
          "value": "Xurshidbek Sobirjonov"
        }
      ],
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      "descriptions": [
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          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eLinux-PAM through 1.7.2 contains an observable timing discrepancy (CWE-208) in the pam_userdb module\u0027s plaintext-password comparison path in modules/pam_userdb/pam_userdb.c that allows a local or network-adjacent attacker able to repeatedly drive authentication through a calling service to recover the plaintext password of a target account by measuring response-timing differences.\u003c/p\u003e"
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              "lang": "en",
              "value": "An attacker who can repeatedly drive authentication through a service that invokes pam_userdb with plaintext-password configuration and without an artificial failure delay can measure response-timing differences to learn the correct password length and recover the plaintext password byte by byte. Recovery requires many measurements per character and is sensitive to scheduling and network jitter; recovery of one user\u0027s secret does not by itself yield access to other accounts. Practical exploitation is gated by an administrative misconfiguration (pam_userdb storing passwords in plaintext, reached when the module is configured with crypt=none, with an unknown crypt method, or with no crypt= option) and by the absence of failure-delay or rate-limiting in the calling service."
            }
          ]
        }
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      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NO",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
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            "attackRequirements": "PRESENT",
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            "exploitMaturity": "PROOF_OF_CONCEPT",
            "privilegesRequired": "NONE",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
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            "subIntegrityImpact": "NONE",
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            "valueDensity": "DIFFUSE",
            "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/AU:N/V:D",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
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            "vulnerabilityResponseEffort": "NOT_DEFINED"
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          "scenarios": [
            {
              "lang": "en",
              "value": "An attacker repeatedly authenticates through a service that calls pam_userdb (plaintext mode) and measures the time the service takes to reject each candidate password to learn the password length and recover the password one byte at a time."
            }
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        {
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            "confidentialityImpact": "HIGH",
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            "scope": "UNCHANGED",
            "userInteraction": "NONE",
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            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
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      "providerMetadata": {
        "dateUpdated": "2026-08-10T11:43:56.355Z",
        "orgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
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          "tags": [
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          ],
          "url": "https://github.com/linux-pam/linux-pam"
        },
        {
          "name": "Vulnerable plaintext-password comparison in pam_userdb.c (master)",
          "tags": [
            "product"
          ],
          "url": "https://github.com/linux-pam/linux-pam/blob/master/modules/pam_userdb/pam_userdb.c#L327"
        },
        {
          "name": "pam_consttime_streq helper available for the remediation",
          "tags": [
            "product"
          ],
          "url": "https://github.com/linux-pam/linux-pam/blob/master/libpam/include/pam_inline.h"
        },
        {
          "name": "CWE-208: Observable Timing Discrepancy",
          "tags": [
            "technical-description"
          ],
          "url": "https://cwe.mitre.org/data/definitions/208.html"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Linux-PAM pam_userdb Observable Timing Discrepancy in Plaintext Password Comparison",
      "x_assigner_notes": "The vulnerable comparison was verified by direct source inspection of modules/pam_userdb/pam_userdb.c at tag v1.7.2 and at master HEAD as of disclosure: lines 327-332 perform a length-equality early exit followed by strncmp() / strncasecmp(). Linux-PAM has previously addressed the same weakness class in a sibling module: NEWS for Release 1.7.0 records \"pam_unix: compare password hashes in constant time\", and Release 1.6.0 hardened pam_mkhomedir \"against timing attacks\". The pam_consttime_streq() helper used by those fixes lives in libpam/include/pam_inline.h, which pam_userdb.c already includes, so the remediation in pam_userdb is a drop-in replacement of the strncmp call. The v1.7.2 release notes do not list a pam_userdb hardening change. Exploitation is gated by (a) the administrator having configured pam_userdb with plaintext password storage (crypt=none, unknown crypt method, or no crypt= option), a discouraged but documented configuration; and (b) the calling service not applying an authentication-failure delay - both gates raise attack complexity and bound real-world impact, so CVSS is scored MEDIUM rather than HIGH consistent with prior CWE-208 timing-leak CVE scoring.",
      "x_author": "Xurshidbek Sobirjonov"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
    "assignerShortName": "TuranSec",
    "cveId": "CVE-2026-54411",
    "datePublished": "2026-06-14T17:21:43.853Z",
    "dateReserved": "2026-06-13T16:39:46.122Z",
    "dateUpdated": "2026-08-10T11:43:56.355Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

usn-8601-1

Vulnerability from osv_ubuntu

Published

2026-07-23 14:49

Modified

2026-07-23 14:49

Summary

pam vulnerability

Details

It was discovered that PAM had a timing discrepancy in the pam_userdb module when comparing plaintext passwords. An attacker could possibly use this issue to obtain sensitive information by measuring response-timing differences during repeated authentication attempts.

References

URL

Type

	https://ubuntu.com/security/notices/USN-8601-1	ADVISORY
	https://ubuntu.com/security/CVE-2026-54411	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-54411",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/AU:N/V:D",
                  "type": "CVSS_V4"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:22.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libpam-cracklib",
            "binary_version": "1.4.0-11ubuntu2.7"
          },
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.4.0-11ubuntu2.7"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.4.0-11ubuntu2.7"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.4.0-11ubuntu2.7"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.4.0-11ubuntu2.7"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.4.0-11ubuntu2.7?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.4.0-11ubuntu2.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.1-5ubuntu11",
        "1.4.0-10ubuntu1",
        "1.4.0-10ubuntu2",
        "1.4.0-11ubuntu1",
        "1.4.0-11ubuntu2",
        "1.4.0-11ubuntu2.1",
        "1.4.0-11ubuntu2.3",
        "1.4.0-11ubuntu2.4",
        "1.4.0-11ubuntu2.5",
        "1.4.0-11ubuntu2.6"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-54411",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/AU:N/V:D",
                  "type": "CVSS_V4"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:24.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.5.3-5ubuntu5.6"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.5.3-5ubuntu5.6"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.5.3-5ubuntu5.6"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.5.3-5ubuntu5.6"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.5.3-5ubuntu5.6?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.5.3-5ubuntu5.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.5.2-6ubuntu1",
        "1.5.2-9.1ubuntu1",
        "1.5.2-9.1ubuntu2",
        "1.5.2-9.1ubuntu3",
        "1.5.3-5ubuntu3",
        "1.5.3-5ubuntu4",
        "1.5.3-5ubuntu5",
        "1.5.3-5ubuntu5.1",
        "1.5.3-5ubuntu5.4",
        "1.5.3-5ubuntu5.5"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-54411",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/AU:N/V:D",
                  "type": "CVSS_V4"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:26.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libpam-modules",
            "binary_version": "1.7.0-5ubuntu3.1"
          },
          {
            "binary_name": "libpam-modules-bin",
            "binary_version": "1.7.0-5ubuntu3.1"
          },
          {
            "binary_name": "libpam-runtime",
            "binary_version": "1.7.0-5ubuntu3.1"
          },
          {
            "binary_name": "libpam0g",
            "binary_version": "1.7.0-5ubuntu3.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "pam",
        "purl": "pkg:deb/ubuntu/pam@1.7.0-5ubuntu3.1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.7.0-5ubuntu3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.7.0-5ubuntu2",
        "1.7.0-5ubuntu3"
      ]
    }
  ],
  "aliases": [],
  "details": "It was discovered that PAM had a timing discrepancy in the pam_userdb\nmodule when comparing plaintext passwords. An attacker could possibly use\nthis issue to obtain sensitive information by measuring response-timing\ndifferences during repeated authentication attempts.",
  "id": "USN-8601-1",
  "modified": "2026-07-23T14:49:52Z",
  "published": "2026-07-23T14:49:52Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8601-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-54411"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "pam vulnerability",
  "upstream": [
    "UBUNTU-CVE-2026-54411"
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

ubuntu-cve-2026-54411

Vulnerability from osv_ubuntu

CVE-2026-54411 (GCVE-0-2026-54411)

usn-8601-1

Vulnerability from osv_ubuntu

Tags

Sightings

Nomenclature