CVE-2021-3738

In DCE/RPC it is possible to share the handles (cookies for resource state) between multiple connections via a mechanism called 'association groups'. These handles can reference connections to our sam.ldb database. However while the database was correctly shared, the user credentials state was only pointed at, and when one connection within that association group ended, the database would be left pointing at an invalid 'struct session_info'. The most likely outcome here is a crash, but it is possible that the use-after-free could instead allow different user state to be pointed at and this might allow more privileged access.

CVSS v3.0 8.8 HIGH
CVSS v2.0 6.5 MEDIUM

8.8^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

6.5^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:S/C:P/I:P/A:P

Exploitability : 8.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://bugzilla.redhat.com/show_bug.cgi?id=2021726	Issue Tracking Third Party Advisory
https://www.samba.org/samba/security/CVE-2021-3738.html	Vendor Advisory
https://bugzilla.samba.org/show_bug.cgi?id=14468	Issue Tracking Patch Vendor Advisory

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Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:samba:samba::::::::
	cpe:2.3:a:samba:samba::::::::
	cpe:2.3:a:samba:samba::::::::

Information

Published : 2022-03-02 15:15

Updated : 2022-03-10 06:59

NVD link : CVE-2021-3738

Mitre link : CVE-2021-3738

JSON object : View

CWE

CWE-416

Use After Free

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Products Affected

samba

samba

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