Published:2021/06/02  Last Updated:2021/06/02
      
        JVN#91691168
        goo blog App fails to restrict custom URL schemes properly
              
      
      Overview
goo blog App fails to restrict custom URL schemes properly.
Products Affected
- goo blog App for Android ver.1.2.25 and earlier
 - goo blog App for iOS ver.1.3.3 and earlier
 
Description
goo blog App by NTT Resonant Incorporated provides the function to access a requested URL using Custom URL Scheme.
The App does not restrict access to the function properly (CWE-284) which may be exploited to direct the App to access any sites.
Impact
A remote attacker may lead a user to access an arbitrary website via the vulnerable App. As a result, the user may become a victim of a phishing attack.
Solution
Update the Application
Update the application to the latest version according to the information provided by the developer.
The developer has released the following versions.
- goo blog App for Android ver.1.2.26
 - goo blog App for iOS ver.1.3.4
 
Vendor Status
| Vendor | Status | Last Update | Vendor Notes | 
|---|---|---|---|
| NTT Resonant Incorporated | Vulnerable | 2021/06/02 | NTT Resonant Incorporated website | 
References
JPCERT/CC Addendum
Vulnerability Analysis by JPCERT/CC
              CVSS v3
              CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
              
                
            
            
                  Base Score:
                  4.3
                
                
              | Attack Vector(AV) | Physical (P) | Local (L) | Adjacent (A) | Network (N) | 
|---|---|---|---|---|
| Attack Complexity(AC) | High (H) | Low (L) | ||
| Privileges Required(PR) | High (H) | Low (L) | None (N) | |
| User Interaction(UI) | Required (R) | None (N) | ||
| Scope(S) | Unchanged (U) | Changed (C) | ||
| Confidentiality Impact(C) | None (N) | Low (L) | High (H) | |
| Integrity Impact(I) | None (N) | Low (L) | High (H) | |
| Availability Impact(A) | None (N) | Low (L) | High (H) | 
                CVSS v2
                AV:N/AC:M/Au:N/C:N/I:P/A:N
                
                  
              
              
                    Base Score:
                    4.3
                  
                  
                | Access Vector(AV) | Local (L) | Adjacent Network (A) | Network (N) | 
|---|---|---|---|
| Access Complexity(AC) | High (H) | Medium (M) | Low (L) | 
| Authentication(Au) | Multiple (M) | Single (S) | None (N) | 
| Confidentiality Impact(C) | None (N) | Partial (P) | Complete (C) | 
| Integrity Impact(I) | None (N) | Partial (P) | Complete (C) | 
| Availability Impact(A) | None (N) | Partial (P) | Complete (C) | 
Credit
Other Information
| JPCERT Alert | 
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| JPCERT Reports | 
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| CERT Advisory | 
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| CPNI Advisory | 
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| TRnotes | 
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| CVE | 
                                    CVE-2021-20728 | 
              
| JVN iPedia | 
                                    JVNDB-2021-000045 |