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Fencer Intel
medium 6.5

CVE-2016-2126 json

Samba version 4.0.0 up to 4.5.2 is vulnerable to privilege elevation due to incorrect handling of the PAC (Privilege Attribute Certificate)…

published 2017-05-11 9 y ago modified 2026-06-17 4 mo ago also EUVD-2016-3229

cvss
6.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
6.6%
EPSS 6.6% chance of exploitation in 30 days, percentile 93%
public exploits
0
none known

Summary

Samba version 4.0.0 up to 4.5.2 is vulnerable to privilege elevation due to incorrect handling of the PAC (Privilege Attribute Certificate) checksum. A remote, authenticated, attacker can cause the winbindd process to crash using a legitimate Kerberos ticket. A local service with access to the winbindd privileged pipe can cause winbindd to cache elevated access permissions.

Patch / fix

  • samba samba 4.3.13, 4.4.8, 4.5.3
  • samba Debian 14, Debian 13, Debian 12 2:4.5.2+dfsg-2

debian advisories DEBIAN-CVE-2016-2126

  • samba Ubuntu 14.04 LTS 2:4.3.11+dfsg-0ubuntu0.14.04.4
  • samba Ubuntu 16.04 LTS 2:4.3.11+dfsg-0ubuntu0.16.04.3

ubuntu advisories UBUNTU-CVE-2016-2126

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • samba RHEL 7 4.4.4-13.el7_3
  • ctdb RHEL 7 4.4.4-13.el7_3
  • samba-dc RHEL 7 4.4.4-13.el7_3
  • ctdb-tests RHEL 7 4.4.4-13.el7_3
  • samba-libs RHEL 7 4.4.4-13.el7_3
  • samba-pidl RHEL 7 4.4.4-13.el7_3
  • samba-test RHEL 7 4.4.4-13.el7_3
  • libwbclient RHEL 7 4.4.4-13.el7_3

red hat advisories RHSA-2017:1265RHSA-2017:0662RHSA-2017:0494RHSA-2017:0495RHSA-2017:0744

  • samba SLES for SAP 12, SLES 12-LTSS, SLE High Availability Extension 12 4.2.4-18.30.1
  • samba SLES for SAP 11 SP4, SLES 11 SP4, SLES 11 SP3-TERADATA +6 more 3.6.3-84.1
  • samba SLES for SAP 12 SP2, SLES for SAP 12 SP1, SLES for Raspberry Pi 12 SP2 +7 more 4.2.4-28.3.1
  • samba SLES for SAP 12 SP2, SLES for Raspberry Pi 12 SP2, SLES 12 SP2 +3 more 4.4.2-31.1
  • samba SLES 11 SP2-LTSS 3.6.3-56.1

suse advisories SUSE-SU-2016:3300-1SUSE-SU-2016:3299-1SUSE-SU-2016:3298-1SUSE-SU-2016:3272-1SUSE-SU-2016:3271-1

  • samba openSUSE Tumbleweed 4.14.6+git.182.2205d5224e3-1.1

opensuse advisories openSUSE-SU-2024:11365-1

  • samba Alpine 3.3, Alpine 3.2 4.2.14-r1
  • samba Alpine 3.4 4.4.5-r2

alpine advisories ALPINE-CVE-2016-2126

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • samba Arch Linux 4.5.3-1

arch linux advisories AVG-111

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2016-2126 updated cvss 3.5

samba: Flaws in Kerberos PAC validation can trigger privilege elevation

  • Red Hat Enterprise Linux 5 samba, samba3x
    affected: no fix planned “Will not fix”
  • Red Hat Enterprise Linux Client (v. 7) samba 4.4.4-13.el7_3, samba-libs 4.4.4-13.el7_3, libwbclient 4.4.4-13.el7_3, libsmbclient 4.4.4-13.el7_3, samba-client 4.4.4-13.el7_3, samba-common 4.4.4-13.el7_3, +7 more Red Hat Enterprise Linux Client Optional (v. 7) samba 4.4.4-13.el7_3, samba-dc 4.4.4-13.el7_3, samba-pidl 4.4.4-13.el7_3, samba-test 4.4.4-13.el7_3, samba-python 4.4.4-13.el7_3, samba-dc-libs 4.4.4-13.el7_3, +3 more Red Hat Enterprise Linux ComputeNode (v. 7) samba 4.4.4-13.el7_3, samba-libs 4.4.4-13.el7_3, libwbclient 4.4.4-13.el7_3, libsmbclient 4.4.4-13.el7_3, samba-client 4.4.4-13.el7_3, samba-common 4.4.4-13.el7_3, +6 more Red Hat Enterprise Linux ComputeNode Optional (v. 7) samba 4.4.4-13.el7_3, samba-dc 4.4.4-13.el7_3, samba-pidl 4.4.4-13.el7_3, samba-test 4.4.4-13.el7_3, samba-python 4.4.4-13.el7_3, samba-dc-libs 4.4.4-13.el7_3, +4 more
    fixed: vendor fix RHSA-2017:1265
  • Red Hat Enterprise Linux Desktop (v. 6) samba 3.6.23-41.el6, samba4 4.2.10-9.el6, samba4-dc 4.2.10-9.el6, samba4-libs 4.2.10-9.el6, samba4-pidl 4.2.10-9.el6, samba4-test 4.2.10-9.el6, +12 more Red Hat Enterprise Linux Desktop Optional (v. 6) samba 3.6.23-41.el6, samba-swat 3.6.23-41.el6, samba-glusterfs 3.6.23-41.el6, samba-domainjoin-gui 3.6.23-41.el6, samba-winbind-krb5-locator 3.6.23-41.el6 Red Hat Enterprise Linux HPC Node (v. 6) samba 3.6.23-41.el6, samba4 4.2.10-9.el6, samba4-dc 4.2.10-9.el6, samba4-libs 4.2.10-9.el6, samba4-pidl 4.2.10-9.el6, samba4-test 4.2.10-9.el6, +11 more Red Hat Enterprise Linux HPC Node Optional (v. 6) samba 3.6.23-41.el6, samba-swat 3.6.23-41.el6, libsmbclient 3.6.23-41.el6, samba-glusterfs 3.6.23-41.el6, samba-domainjoin-gui 3.6.23-41.el6, samba-winbind-krb5-locator 3.6.23-41.el6 Red Hat Enterprise Linux Server (v. 6) samba 3.6.23-41.el6, samba4 4.2.10-9.el6, samba4-dc 4.2.10-9.el6, samba4-libs 4.2.10-9.el6, samba4-pidl 4.2.10-9.el6, samba4-test 4.2.10-9.el6, +12 more
    fixed: vendor fix RHSA-2017:0662
  • Red Hat Enterprise Linux Server (v. 7) samba 4.4.4-13.el7_3, samba-libs 4.4.4-13.el7_3, libwbclient 4.4.4-13.el7_3, libsmbclient 4.4.4-13.el7_3, samba-client 4.4.4-13.el7_3, samba-common 4.4.4-13.el7_3, +8 more
    fixed: vendor fix RHSA-2017:1265
  • Red Hat Enterprise Linux Server Optional (v. 6) samba-swat 3.6.23-41.el6, samba-glusterfs 3.6.23-41.el6, samba-domainjoin-gui 3.6.23-41.el6, samba-winbind-krb5-locator 3.6.23-41.el6
    fixed: vendor fix RHSA-2017:0662
  • Red Hat Enterprise Linux Server Optional (v. 7) samba-dc 4.4.4-13.el7_3, samba-pidl 4.4.4-13.el7_3, samba-test 4.4.4-13.el7_3, samba-python 4.4.4-13.el7_3, samba-dc-libs 4.4.4-13.el7_3, samba-test-libs 4.4.4-13.el7_3, +2 more Red Hat Enterprise Linux Server Resilient Storage (v. 7) ctdb 4.4.4-13.el7_3, ctdb-tests 4.4.4-13.el7_3
    fixed: vendor fix RHSA-2017:1265
  • Red Hat Enterprise Linux Workstation (v. 6) samba 3.6.23-41.el6, samba4 4.2.10-9.el6, samba4-dc 4.2.10-9.el6, samba4-libs 4.2.10-9.el6, samba4-pidl 4.2.10-9.el6, samba4-test 4.2.10-9.el6, +12 more
    fixed: vendor fix RHSA-2017:0662
  • Red Hat Enterprise Linux Workstation (v. 7) samba 4.4.4-13.el7_3, samba-libs 4.4.4-13.el7_3, libwbclient 4.4.4-13.el7_3, libsmbclient 4.4.4-13.el7_3, samba-client 4.4.4-13.el7_3, samba-common 4.4.4-13.el7_3, +8 more
    fixed: vendor fix RHSA-2017:1265
show 4 more
  • Red Hat Enterprise Linux Workstation Optional (v. 6) samba-swat 3.6.23-41.el6, samba-glusterfs 3.6.23-41.el6, samba-domainjoin-gui 3.6.23-41.el6, samba-winbind-krb5-locator 3.6.23-41.el6
    fixed: vendor fix RHSA-2017:0662
  • Red Hat Enterprise Linux Workstation Optional (v. 7) samba-dc 4.4.4-13.el7_3, samba-pidl 4.4.4-13.el7_3, samba-test 4.4.4-13.el7_3, samba-dc-libs 4.4.4-13.el7_3, samba-test-libs 4.4.4-13.el7_3, samba-vfs-glusterfs 4.4.4-13.el7_3, +1 more
    fixed: vendor fix RHSA-2017:1265
  • Red Hat Gluster 3.2 Samba on RHEL-6 ctdb 4.4.6-4.el6rhs, samba 4.4.6-4.el6rhs, samba-dc 4.4.6-4.el6rhs, ctdb-tests 4.4.6-4.el6rhs, samba-libs 4.4.6-4.el6rhs, samba-pidl 4.4.6-4.el6rhs, +17 more
    fixed: vendor fix RHSA-2017:0494
  • Red Hat Gluster 3.2 Samba on RHEL-7 ctdb 4.4.6-4.el7rhgs, samba 4.4.6-4.el7rhgs, samba-dc 4.4.6-4.el7rhgs, ctdb-tests 4.4.6-4.el7rhgs, samba-libs 4.4.6-4.el7rhgs, samba-pidl 4.4.6-4.el7rhgs, +17 more
    fixed: vendor fix RHSA-2017:0495

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

6.59% chance of exploitation in the next 30 days, higher than 93% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 4.0 AV:N/AC:L/Au:S/C:N/I:N/A:P

Classification

Weakness
  • CWE-264 Permissions, Privileges, and Access Controls

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.