CVE-2018-17071

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

18/09/2018

Last modified:

10/12/2018

Description

The fallback function of a simple lottery smart contract implementation for Lucky9io, an Ethereum gambling game, generates a random value with the publicly readable variable entry_number. This variable is private, yet it is readable by eth.getStorageAt function. Also, attackers can purchase a ticket at a low price by directly calling the fallback function with small msg.value, because the developer set the currency unit incorrectly. Therefore, it allows attackers to always win and get rewards.

Impact

Vector 3.x

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N CVSS v3.1 Severity and Metrics:

Base Score: 7.50 HIGH
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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

Base Score 3.x

7.50

Severity 3.x

HIGH

Vector 2.0

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

Base Score: 5.00 MEDIUM
Vector: AV:N/AC:L/Au:N/C:P/I:N/A:N

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

Base Score 2.0

5.00

Severity 2.0

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:lucky9:lucky9io:-:::::::*

To consult the complete list of CPE names with products and versions, see this page

References to Advisories, Solutions, and Tools

https://github.com/TEAM-C4B/CVE-LIST/tree/master/CVE-2018-17071