CVE-2021-27217

Severity CVSS v4.0:

Pending analysis

Type:

CWE-125 Out-of-bounds Read

Publication date:

04/03/2021

Last modified:

26/03/2021

Description

An issue was discovered in the _send_secure_msg() function of Yubico yubihsm-shell through 2.0.3. The function does not correctly validate the embedded length field of an authenticated message received from the device. Out-of-bounds reads performed by aes_remove_padding() can crash the running process, depending on the memory layout. This could be used by an attacker to cause a client-side denial of service. The yubihsm-shell project is included in the YubiHSM 2 SDK product.

Impact

Vector 3.x

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

Base Score: 4.40 MEDIUM
Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H

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

Base Score 3.x

4.40

Severity 3.x

MEDIUM

Vector 2.0

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

Base Score: 3.50 LOW
Vector: AV:N/AC:M/Au:S/C:N/I:N/A:P

Attack Vector (AV): Network
Attack Complexity (AC): Medium
Authentication (Au): Single
Confidentiality (C): None
Integrity (I): None
Availability (A): Physical