CVE-2020-4044

Severity CVSS v4.0:

Pending analysis

Type:

CWE-121 Stack-based Buffer Overflow

Publication date:

30/06/2020

Last modified:

14/08/2020

Description

The xrdp-sesman service before version 0.9.13.1 can be crashed by connecting over port 3350 and supplying a malicious payload. Once the xrdp-sesman process is dead, an unprivileged attacker on the server could then proceed to start their own imposter sesman service listening on port 3350. This will allow them to capture any user credentials that are submitted to XRDP and approve or reject arbitrary login credentials. For xorgxrdp sessions in particular, this allows an unauthorized user to hijack an existing session. This is a buffer overflow attack, so there may be a risk of arbitrary code execution as well.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 7.80 HIGH
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x

7.80

Severity 3.x

HIGH

Vector 2.0

AV:L/AC:L/Au:N/C:P/I:P/A:P CVSS v2.0 Severity and Metrics:

Base Score: 4.60 MEDIUM
Vector: AV:L/AC:L/Au:N/C:P/I:P/A:P

Attack Vector (AV): Local
Attack Complexity (AC): Low
Authentication (Au): None
Confidentiality (C): Physical
Integrity (I): Physical
Availability (A): Physical