USN-8621-1

It was discovered that Samba's pam_winbind incorrectly handled home directory ownership when mkhomedir was enabled. A local attacker could possibly use this issue to cause a denial of service by triggering a change in ownership of the root directory. (CVE-2026-15779)

Arjun Basnet, Douglas Bagnall, and Andrew Tridgell discovered that Samba incorrectly handled TSIG packets with name compression. A remote attacker could possibly use this issue to cause Samba to crash, resulting in a denial of service. (CVE-2026-6949)

Tristan Madani discovered that Samba incorrectly handled malformed ASN.1 kpasswd packets. An authenticated user could possibly use this issue to cause Samba to crash, resulting in a denial of service. (CVE-2026-58216)

Andrew Tridgell and Tristan Madani discovered that Samba incorrectly handled TKEY name registration. A remote attacker could possibly use this issue to exhaust the TKEY name cache, resulting in a denial of service. (CVE-2026-58218)

It was discovered that Samba incorrectly handled internal LDB special directory names when processing authenticated LDAP requests. An authenticated user could possibly use this issue to perform unauthorized modifications and gain control of a domain. (CVE-2026-58221)

Andrew Tridgell and Tristan Madani discovered that Samba incorrectly handled LDAP Compare requests. An authenticated user could possibly use this issue to obtain sensitive information. (CVE-2026-58222)

Tristan Madani, Andrew Tridgell, and Martin Schwenke discovered that the CTDB protocol in Samba had insufficient bounds checking. A remote attacker could possibly use this issue to cause Samba to crash, resulting in a denial of service. (CVE-2026-58224)

References

Affected packages

Ubuntu:22.04:LTS / samba

Package

Name: samba
Purl: pkg:deb/ubuntu/samba?arch=source&distro=jammy

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

2:4.15.13+dfsg-0ubuntu1.13

Affected versions

2:4.*

2:4.13.5+dfsg-2ubuntu2

2:4.13.5+dfsg-2ubuntu3

2:4.13.14+dfsg-0ubuntu1

2:4.13.14+dfsg-0ubuntu2

2:4.15.5~dfsg-0ubuntu1

2:4.15.5~dfsg-0ubuntu2

2:4.15.5~dfsg-0ubuntu4

2:4.15.5~dfsg-0ubuntu5

2:4.15.5~dfsg-0ubuntu5.1

2:4.15.9+dfsg-0ubuntu0.2

2:4.15.9+dfsg-0ubuntu0.3

2:4.15.13+dfsg-0ubuntu1

2:4.15.13+dfsg-0ubuntu1.1

2:4.15.13+dfsg-0ubuntu1.2

2:4.15.13+dfsg-0ubuntu1.3

2:4.15.13+dfsg-0ubuntu1.4

2:4.15.13+dfsg-0ubuntu1.5

2:4.15.13+dfsg-0ubuntu1.6

2:4.15.13+dfsg-0ubuntu1.7

2:4.15.13+dfsg-0ubuntu1.8

2:4.15.13+dfsg-0ubuntu1.9

2:4.15.13+dfsg-0ubuntu1.10

2:4.15.13+dfsg-0ubuntu1.12

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "ctdb"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "libnss-winbind"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "libpam-winbind"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "libsmbclient"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "libwbclient0"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "python3-samba"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "registry-tools"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "samba"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "samba-common"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "samba-common-bin"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "samba-dsdb-modules"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "samba-libs"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "samba-testsuite"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "samba-vfs-modules"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "smbclient"
        },
        {
            "binary_version": "2:4.15.13+dfsg-0ubuntu1.13",
            "binary_name": "winbind"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8621-1.json"

cves_map

{
    "ecosystem": "Ubuntu:22.04:LTS",
    "cves": [
        {
            "id": "CVE-2026-6949",
            "severity": [
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-15779",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58216",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58218",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58221",
            "severity": [
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58222",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58224",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}

Ubuntu:24.04:LTS / samba

Package

Name: samba
Purl: pkg:deb/ubuntu/samba?arch=source&distro=noble

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

2:4.19.5+dfsg-4ubuntu9.7

Affected versions

2:4.*

2:4.18.6+dfsg-1ubuntu2

2:4.18.6+dfsg-1ubuntu2.1

2:4.18.6+dfsg-1ubuntu2.2

2:4.19.4+dfsg-3ubuntu1

2:4.19.5+dfsg-1ubuntu1

2:4.19.5+dfsg-4ubuntu7

2:4.19.5+dfsg-4ubuntu8

2:4.19.5+dfsg-4ubuntu9

2:4.19.5+dfsg-4ubuntu9.2

2:4.19.5+dfsg-4ubuntu9.3

2:4.19.5+dfsg-4ubuntu9.4

2:4.19.5+dfsg-4ubuntu9.6

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "ctdb"
        },
        {
            "binary_version": "2:2.8.0+samba4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "ldb-tools"
        },
        {
            "binary_version": "2:2.8.0+samba4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "libldb2"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "libnss-winbind"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "libpam-winbind"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "libsmbclient0"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "libwbclient0"
        },
        {
            "binary_version": "2:2.8.0+samba4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "python3-ldb"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "python3-samba"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "registry-tools"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba-ad-dc"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba-ad-provision"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba-common"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba-common-bin"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba-dsdb-modules"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba-libs"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba-testsuite"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba-vfs-modules"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "samba-vfs-modules-extra"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "smbclient"
        },
        {
            "binary_version": "2:4.19.5+dfsg-4ubuntu9.7",
            "binary_name": "winbind"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8621-1.json"

cves_map

{
    "ecosystem": "Ubuntu:24.04:LTS",
    "cves": [
        {
            "id": "CVE-2026-6949",
            "severity": [
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-15779",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58216",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58218",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58221",
            "severity": [
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58222",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58224",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}

Ubuntu:26.04:LTS / samba

Package

Name: samba
Purl: pkg:deb/ubuntu/samba?arch=source&distro=resolute

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

2:4.23.6+dfsg-1ubuntu2.2

Affected versions

2:4.*

2:4.22.3+dfsg-4ubuntu2

2:4.22.3+dfsg-4ubuntu2.1

2:4.22.3+dfsg-4ubuntu3

2:4.22.3+dfsg-4ubuntu4

2:4.23.4+dfsg-1ubuntu1

2:4.23.5+dfsg-1ubuntu2

2:4.23.6+dfsg-1ubuntu1

2:4.23.6+dfsg-1ubuntu2

2:4.23.6+dfsg-1ubuntu2.1

Ecosystem specific

{
    "availability": "No subscription required",
    "binaries": [
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "ctdb"
        },
        {
            "binary_version": "2:2.11.0+samba4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "ldb-tools"
        },
        {
            "binary_version": "2:2.11.0+samba4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "libldb2"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "libnss-winbind"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "libpam-winbind"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "libsmbclient0"
        },
        {
            "binary_version": "2:2.4.3+samba4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "libtalloc2"
        },
        {
            "binary_version": "2:1.4.14+samba4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "libtdb1"
        },
        {
            "binary_version": "2:0.17.1+samba4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "libtevent0t64"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "libwbclient0"
        },
        {
            "binary_version": "2:2.11.0+samba4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "python3-ldb"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "python3-samba"
        },
        {
            "binary_version": "2:2.4.3+samba4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "python3-talloc"
        },
        {
            "binary_version": "2:1.4.14+samba4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "python3-tdb"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "registry-tools"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-ad-dc"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-ad-provision"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-common"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-common-bin"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-dsdb-modules"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-libs"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-testsuite"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-vfs-ceph"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-vfs-glusterfs"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-vfs-modules"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "samba-vfs-modules-extra"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "smbclient"
        },
        {
            "binary_version": "2:1.4.14+samba4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "tdb-tools"
        },
        {
            "binary_version": "2:4.23.6+dfsg-1ubuntu2.2",
            "binary_name": "winbind"
        }
    ]
}

Database specific

source

"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8621-1.json"

cves_map

{
    "ecosystem": "Ubuntu:26.04:LTS",
    "cves": [
        {
            "id": "CVE-2026-6949",
            "severity": [
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-15779",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58216",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58218",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58221",
            "severity": [
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58222",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        },
        {
            "id": "CVE-2026-58224",
            "severity": [
                {
                    "type": "CVSS_V3",
                    "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
                },
                {
                    "type": "Ubuntu",
                    "score": "medium"
                }
            ]
        }
    ]
}