CVE-2021-20835
CVE-2021-20835 is a high-severity vulnerability in Mercari with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-862.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (68th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-862
- Affected product: Mercari
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is CVE-2021-20835?
- 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.
- How severe is CVE-2021-20835?
- CVE-2021-20835 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2021-20835 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-20835?
- CVE-2021-20835 affects Mercari. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-20835?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-20835 published?
- CVE-2021-20835 was published on 2021-11-24 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:mercari:mercari:*:*:*:*:*:android:*:*
More vulnerabilities in Mercari
- CVE-2020-5604 — High (CVSS 8.1): Android App 'Mercari' (Japan version) prior to version 3.52.0 allows arbitrary method execution of a Java object by a…
- CVE-2024-23388 — Medium (CVSS 6.1): Improper authorization in handler for custom URL scheme issue in "Mercari" App for Android prior to version 5.78.0…
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