Vulnerability-Lookup

OESA-2026-3412 (CVE-2026-15779)

Vulnerability from osv_openeuler – Published: 2026-08-20 09:54 – Updated: 2026-08-20 09:54 – Source website

Summary

samba security update

Details

Samba is a suite of programs for Linux and Unix to interoperate with Windows.

Security Fix(es):

A flaw was found in samba's pam_winbind. When mkhomedir is enabled, pam_winbind chowns the target account's home directory without validating the path is not a critical system directory such as /. On affected systems, accounts with / as their home directory (a common default for system accounts) can have this triggered not only by root, but by a non-root user holding a narrow sudo delegation to run commands as that account, causing ownership of / to change and resulting in severe denial of service (SSH, sudo, and package-manager failures). The change does not grant write access to / (which ships with restrictive 0555 permissions on RHEL), so the impact is availability loss rather than further privilege escalation.(CVE-2026-15779)

Severity

6.1 (Medium)


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

References

URL

Type

	https://www.openeuler.org/zh/security/security-bu…	ADVISORY
	https://nvd.nist.gov/vuln/detail/CVE-2026-15779	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "ctdb-4.19.3-11.oe2403sp4.aarch64.rpm",
          "libsmbclient-4.19.3-11.oe2403sp4.aarch64.rpm",
          "libsmbclient-devel-4.19.3-11.oe2403sp4.aarch64.rpm",
          "libwbclient-4.19.3-11.oe2403sp4.aarch64.rpm",
          "libwbclient-devel-4.19.3-11.oe2403sp4.aarch64.rpm",
          "python3-samba-4.19.3-11.oe2403sp4.aarch64.rpm",
          "python3-samba-dc-4.19.3-11.oe2403sp4.aarch64.rpm",
          "python3-samba-test-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-client-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-client-libs-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-common-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-common-tools-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-dc-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-dc-bind-dlz-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-dc-libs-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-dc-provision-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-debuginfo-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-debugsource-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-devel-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-help-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-krb5-printing-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-libs-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-test-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-tools-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-usershares-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-winbind-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-winbind-clients-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-winbind-krb5-locator-4.19.3-11.oe2403sp4.aarch64.rpm",
          "samba-winbind-modules-4.19.3-11.oe2403sp4.aarch64.rpm"
        ],
        "noarch": [
          "samba-pidl-4.19.3-11.oe2403sp4.noarch.rpm"
        ],
        "src": [
          "samba-4.19.3-11.oe2403sp4.src.rpm"
        ],
        "x86_64": [
          "ctdb-4.19.3-11.oe2403sp4.x86_64.rpm",
          "libsmbclient-4.19.3-11.oe2403sp4.x86_64.rpm",
          "libsmbclient-devel-4.19.3-11.oe2403sp4.x86_64.rpm",
          "libwbclient-4.19.3-11.oe2403sp4.x86_64.rpm",
          "libwbclient-devel-4.19.3-11.oe2403sp4.x86_64.rpm",
          "python3-samba-4.19.3-11.oe2403sp4.x86_64.rpm",
          "python3-samba-dc-4.19.3-11.oe2403sp4.x86_64.rpm",
          "python3-samba-test-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-client-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-client-libs-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-common-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-common-tools-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-dc-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-dc-bind-dlz-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-dc-libs-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-dc-provision-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-debuginfo-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-debugsource-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-devel-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-help-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-krb5-printing-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-libs-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-test-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-tools-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-usershares-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-vfs-glusterfs-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-winbind-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-winbind-clients-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-winbind-krb5-locator-4.19.3-11.oe2403sp4.x86_64.rpm",
          "samba-winbind-modules-4.19.3-11.oe2403sp4.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP4",
        "name": "samba",
        "purl": "pkg:rpm/openEuler/samba\u0026distro=openEuler-24.03-LTS-SP4"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.19.3-11.oe2403sp4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Medium"
  },
  "details": "Samba is a suite of programs for Linux and Unix to interoperate with Windows.\r\n\r\nSecurity Fix(es):\n\nA flaw was found in samba\u0026apos;s pam_winbind. When mkhomedir is enabled, pam_winbind chowns the target account\u0026apos;s home directory without validating the path is not a critical system directory such as /. On affected systems, accounts with / as their home directory (a common default for system accounts) can have this triggered not only by root, but by a non-root user holding a narrow sudo delegation to run commands as that account, causing ownership of / to change and resulting in severe denial of service (SSH, sudo, and package-manager failures). The change does not grant write access to / (which ships with restrictive 0555 permissions on RHEL), so the impact is availability loss rather than further privilege escalation.(CVE-2026-15779)",
  "id": "OESA-2026-3412",
  "modified": "2026-08-20T09:54:50Z",
  "published": "2026-08-20T09:54:50Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3412"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-15779"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "samba security update",
  "upstream": [
    "CVE-2026-15779"
  ]
}

CVE-2026-15779 (GCVE-0-2026-15779)

Vulnerability from cvelistv5 – Published: 2026-07-15 12:33 – Updated: 2026-07-15 13:04

Title

Samba-winbind: samba: pam_winbind mkhomedir chowns critical system paths without validation

Summary

Severity

6.1 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-15 13:04 UTC

CWE

CWE-732 - Incorrect Permission Assignment for Critical Resource

Assigner

redhat redhat root Scorecard

References

5 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-15779	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2499991	issue-trackingx_refsource_REDHAT
https://gitlab.com/samba-team/samba/-/blob/samba-…
https://gitlab.com/samba-team/samba/-/blob/samba-…
https://gitlab.com/samba-team/samba/-/blob/samba-…

Impacted products

5 products

Vendor	Product	Version
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Date Public

2026-07-14 00:00

Credits

This issue was discovered by Runar Lundgren (Red Hat).

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-15779",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-15T13:04:26.614098Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-15T13:04:49.311Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
          "defaultStatus": "affected",
          "packageName": "samba-winbind",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:6"
          ],
          "defaultStatus": "unknown",
          "packageName": "samba-winbind",
          "product": "Red Hat Enterprise Linux 6",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:7"
          ],
          "defaultStatus": "affected",
          "packageName": "samba-winbind",
          "product": "Red Hat Enterprise Linux 7",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:8"
          ],
          "defaultStatus": "affected",
          "packageName": "samba-winbind",
          "product": "Red Hat Enterprise Linux 8",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:9"
          ],
          "defaultStatus": "affected",
          "packageName": "samba-winbind",
          "product": "Red Hat Enterprise Linux 9",
          "vendor": "Red Hat"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "This issue was discovered by Runar Lundgren (Red Hat)."
        }
      ],
      "datePublic": "2026-07-14T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "A flaw was found in samba\u0027s pam_winbind. When mkhomedir is enabled, pam_winbind chowns the target account\u0027s home directory without validating the path is not a critical system directory such as /. On affected systems, accounts with / as their home directory (a common default for system accounts) can have this triggered not only by root, but by a non-root user holding a narrow sudo delegation to run commands as that account, causing ownership of / to change and resulting in severe denial of service (SSH, sudo, and package-manager failures). The change does not grant write access to / (which ships with restrictive 0555 permissions on RHEL), so the impact is availability loss rather than further privilege escalation."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "namespace": "https://access.redhat.com/security/updates/classification/",
              "value": "Moderate"
            },
            "type": "Red Hat severity rating"
          }
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 6.1,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-732",
              "description": "Incorrect Permission Assignment for Critical Resource",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-15T12:33:04.688Z",
        "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "shortName": "redhat"
      },
      "references": [
        {
          "tags": [
            "vdb-entry",
            "x_refsource_REDHAT"
          ],
          "url": "https://access.redhat.com/security/cve/CVE-2026-15779"
        },
        {
          "name": "RHBZ#2499991",
          "tags": [
            "issue-tracking",
            "x_refsource_REDHAT"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2499991"
        },
        {
          "url": "https://gitlab.com/samba-team/samba/-/blob/samba-4.19.4/nsswitch/pam_winbind.c"
        },
        {
          "url": "https://gitlab.com/samba-team/samba/-/blob/samba-4.23.5/nsswitch/pam_winbind.c#L1622"
        },
        {
          "url": "https://gitlab.com/samba-team/samba/-/blob/samba-4.24.3/nsswitch/pam_winbind.c#L1590"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-05-21T00:00:00.000Z",
          "value": "Reported to Red Hat."
        },
        {
          "lang": "en",
          "time": "2026-07-14T00:00:00.000Z",
          "value": "Made public."
        }
      ],
      "title": "Samba-winbind: samba: pam_winbind mkhomedir chowns critical system paths without validation",
      "workarounds": [
        {
          "lang": "en",
          "value": "Do not enable mkhomedir in pam_winbind.conf on systems where any account (including system accounts) may resolve to a home directory of / or another sensitive system path."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
      },
      "x_redhatCweChain": "CWE-732: Incorrect Permission Assignment for Critical Resource"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
    "cveId": "CVE-2026-15779",
    "datePublished": "2026-07-15T12:33:04.688Z",
    "dateReserved": "2026-07-14T18:33:36.712Z",
    "dateUpdated": "2026-07-15T13:04:49.311Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

OESA-2026-3412 (CVE-2026-15779)

CVE-2026-15779 (GCVE-0-2026-15779)

Tags

Sightings

Nomenclature

Related by attack behaviour