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.
CVE-2016-2126
MEDIUMNVD 6.56.5—
EchelonGraph scoreMEDIUM confidence
Score 6.5 from GitHub Security Advisory published 2022-05-14. NVD baseline CVSS 6.5; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
6.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 7%CVSS: 6.5Exploit: NoneExposed: 0
A fix is available — apply it.
- CVSS v3
- 6.5
- EG Score
- 6.5(medium)
- EPSS
- 93.0%
- KEV
- Not listed
Published
May 11, 2017
Last Modified
May 13, 2026
References (18)
- secalert@redhathttp://rhn.redhat.com/errata/RHSA-2017-0494.html
- secalert@redhathttp://rhn.redhat.com/errata/RHSA-2017-0495.html
- secalert@redhathttp://rhn.redhat.com/errata/RHSA-2017-0662.html
- secalert@redhathttp://rhn.redhat.com/errata/RHSA-2017-0744.html
- secalert@redhathttp://www.securityfocus.com/bid/94994
- secalert@redhathttp://www.securitytracker.com/id/1037495
- secalert@redhathttps://access.redhat.com/errata/RHSA-2017:1265
- secalert@redhathttps://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA43730
- secalert@redhathttps://www.samba.org/samba/security/CVE-2016-2126.html
- af854a3a-2127-422b-91ae-364da2661108http://rhn.redhat.com/errata/RHSA-2017-0494.html
- af854a3a-2127-422b-91ae-364da2661108http://rhn.redhat.com/errata/RHSA-2017-0495.html
- af854a3a-2127-422b-91ae-364da2661108http://rhn.redhat.com/errata/RHSA-2017-0662.html
- af854a3a-2127-422b-91ae-364da2661108http://rhn.redhat.com/errata/RHSA-2017-0744.html
- af854a3a-2127-422b-91ae-364da2661108http://www.securityfocus.com/bid/94994
- af854a3a-2127-422b-91ae-364da2661108http://www.securitytracker.com/id/1037495
Vendor Advisories for CVE-2016-2126(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Patch Availability(6)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| ubuntu | winbind (2:4.4.5+dfsg-2ubuntu5.2) @ yakkety | 2026-05-22 | ubuntu |
| redhat | samba-0:4.4.4-13.el7_3 | 2017-05-22 | redhat |
| redhat | samba-0:4.4.6-4.el6rhs | 2017-03-23 | redhat |
| redhat | samba-0:4.4.6-4.el7rhgs | 2017-03-23 | redhat |
| redhat | samba-0:3.6.23-41.el6 | 2017-03-21 | redhat |
| redhat | samba4-0:4.2.10-9.el6 | 2017-03-21 | redhat |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Additional Vendor Advisories
(5)
Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.
Frequently asked(5)
What is CVE-2016-2126?
CVE-2016-2126 is a medium vulnerability published on May 11, 2017. 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…
When was CVE-2016-2126 disclosed?
CVE-2016-2126 was first published in the National Vulnerability Database on May 11, 2017, with the most recent update on May 13, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2016-2126 actively exploited?
CVE-2016-2126 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 93.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2016-2126?
CVE-2016-2126 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2016-2126?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2016-2126, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2016-2126
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