MyCryptoChamp randMod Smart Contract weak prng

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in MyCryptoChamp. The affected element is the function randMod. The manipulation as part of Smart Contract leads to weak prng. This vulnerability is documented as CVE-2018-12885. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in MyCryptoChamp (affected version unknown) and classified as critical. This issue affects the function randMod. The manipulation as part of a Smart Contract leads to a weak prng vulnerability. Using CWE to declare the problem leads to CWE-338. The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG's algorithm is not cryptographically strong. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The randMod() function of the smart contract implementation for MyCryptoChamp, an Ethereum game, generates a random value with publicly readable variables such as the current block information and a private variable, (which can be read with a getStorageAt call). Therefore, attackers can get powerful champs/items and get rewards.

The bug was discovered 07/31/2018. The weakness was released 08/07/2018 (Website). It is possible to read the advisory at etherscan.io. The identification of this vulnerability is CVE-2018-12885 since 06/26/2018. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1600.001 according to MITRE ATT&CK.

The vulnerability was handled as a non-public zero-day exploit for at least 7 days. During that time the estimated underground price was around $0-$5k.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.7

VulDB Base Score: 5.6
VulDB Temp Score: 5.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Weak prng
CWE: CWE-338 / CWE-331 / CWE-330
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

06/26/2018 🔍
07/31/2018 +35 days 🔍
08/07/2018 +6 days 🔍
08/07/2018 +0 days 🔍
08/08/2018 +1 days 🔍
03/14/2020 +584 days 🔍

Sourcesinfo

Advisory: etherscan.io
Status: Not defined

CVE: CVE-2018-12885 (🔍)
GCVE (CVE): GCVE-0-2018-12885
GCVE (VulDB): GCVE-100-122711

Entryinfo

Created: 08/08/2018 08:00
Updated: 03/14/2020 07:37
Changes: 08/08/2018 08:00 (55), 03/14/2020 07:37 (1)
Complete: 🔍
Cache ID: 216::103

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