What is CVE-2018-16841?

CVE-2018-16841 is a medium-severity vulnerability in Samba, classified under Use After Free. CVSS score: 6.5/10. Published 2018-11-28.

How severe is CVE-2018-16841?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Is CVE-2018-16841 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Use After Free in Samba

CVE-2018-16841

Samba from version 4.3.0 and before versions 4.7.12, 4.8.7 and 4.9.3 are vulnerable to a denial of service. When configured to accept smart-card authentication, Samba's KDC will call talloc_free() twice on the same memory if the principal in a validly signed certificate does not match the principal in the AS-REQ. This is only possible after authentication with a trusted certificate. talloc is robust against further corruption from a double-free with talloc_free() and directly calls abort(), terminating the KDC process.

Vulnerability class: Use-After-Free

EPSS: 0.046 (90.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Samba
[Unknown] Samba — versions 4.9.3, 4.8.7, 4.7.12
Canonical Ubuntu_linux — versions 12.04, 14.04, 16.04
Debian Debian_linux — versions 9.0

Weakness classification (CWE)

Public proof-of-concept exploits

ARPSyndicate/cve-scores

References

secalert@redhat.com (VDB Entry, Third Party Advisory, vdb-entry, x_refsource_BID)
secalert@redhat.com (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
secalert@redhat.com (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
secalert@redhat.com (x_refsource_CONFIRM, Third Party Advisory)
secalert@redhat.com (x_refsource_CONFIRM, Third Party Advisory, Issue Tracking)
secalert@redhat.com (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
secalert@redhat.com (x_refsource_CONFIRM, Patch, Vendor Advisory)
secalert@redhat.com (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)

Frequently asked questions

What is CVE-2018-16841?: CVE-2018-16841 is a medium-severity vulnerability in Samba, classified under Use After Free. CVSS score: 6.5/10. Published 2018-11-28.
How severe is CVE-2018-16841?: Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2018-16841 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.