What is the CVSS score of CVE-2021-20835?

CVE-2021-20835 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. EPSS exploitation probability: 1.3%.

Mercari CVE-2021-20835

HIGH

Missing Authorization (CWE-862)

2021-11-24 vultures@jpcert.or.jp

Google Authentication Bypass Mercari

7.5

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

7.5 HIGH

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Lifecycle Timeline

CVE Published

Nov 24, 2021 - 16:15 nvd

HIGH 7.5

DescriptionNVD

Improper authorization in handler for custom URL scheme vulnerability in Android App 'Mercari (Merpay) - Marketplace and Mobile Payments App' (Japan version) versions prior to 4.49.1 allows a remote attacker to lead a user to access an arbitrary website and the website launches an arbitrary Activity of the app via the vulnerable App, which may result in Mercari account's access token being obtained.

AnalysisAI

Improper authorization in handler for custom URL scheme vulnerability in Android App 'Mercari (Merpay) - Marketplace and Mobile Payments App' (Japan version) versions prior to 4.49.1 allows a remote. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified as Missing Authorization (CWE-862), which allows attackers to access resources or perform actions without proper authorization checks. Improper authorization in handler for custom URL scheme vulnerability in Android App 'Mercari (Merpay) - Marketplace and Mobile Payments App' (Japan version) versions prior to 4.49.1 allows a remote attacker to lead a user to access an arbitrary website and the website launches an arbitrary Activity of the app via the vulnerable App, which may result in Mercari account's access token being obtained. Affected products include: Mercari. Version information: prior to 4.49.1.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Implement role-based access control, validate authorization on every request server-side, apply principle of least privilege.