CVE-2018-16841

moderate-risk
Published 2018-11-28

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.

Do I need to act?

~
7.1% chance of exploitation in next 30 days
EPSS score — moderate exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
6
CVSS 6.5/10 Medium
NETWORK / LOW complexity

Affected Products (7)

Affected Vendors

Debian Samba Canonical

References (16)

Third Party Advisory http://www.securityfocus.com/bid/106023
Issue Tracking https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16841
Third Party Advisory https://security.gentoo.org/glsa/202003-52
Third Party Advisory https://security.netapp.com/advisory/ntap-20181127-0001/
Third Party Advisory https://usn.ubuntu.com/3827-1/
Third Party Advisory https://usn.ubuntu.com/3827-2/
Third Party Advisory https://www.debian.org/security/2018/dsa-4345
Patch https://www.samba.org/samba/security/CVE-2018-16841.html
Third Party Advisory http://www.securityfocus.com/bid/106023
Issue Tracking https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16841
Third Party Advisory https://security.gentoo.org/glsa/202003-52
Third Party Advisory https://security.netapp.com/advisory/ntap-20181127-0001/
Third Party Advisory https://usn.ubuntu.com/3827-1/
Third Party Advisory https://usn.ubuntu.com/3827-2/
Third Party Advisory https://www.debian.org/security/2018/dsa-4345
Patch https://www.samba.org/samba/security/CVE-2018-16841.html
47
/ 100
moderate-risk
Severity 24/34 · High
Exploitability 9/34 · Low
Exposure 14/34 · Moderate