Google Android up to 8.1 cryptfs.cpp persist_set_key out-of-bounds write

Summaryinfo

A vulnerability was found in Google Android 7.0/7.1.1/7.1.2/8.0/8.1. It has been rated as critical. Affected is the function persist_set_key of the file cryptfs.cpp. This manipulation causes out-of-bounds write. This vulnerability is tracked as CVE-2018-9559. The attack is restricted to local execution. No exploit exists. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability has been found in Google Android 7.0/7.1.1/7.1.2/8.0/8.1 (Smartphone Operating System) and classified as critical. Affected by this vulnerability is the function persist_set_key of the file cryptfs.cpp. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In persist_set_key and other functions of cryptfs.cpp, there is a possible out-of-bounds write due to an uncaught error. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation. Product: Android. Versions: Android-7.0 Android-7.1.1 Android-7.1.2 Android-8.0 Android-8.1 Android-9. Android ID: A-112731440.

The bug was discovered 12/05/2018. The weakness was disclosed 12/06/2018 (Website). It is possible to read the advisory at source.android.com. This vulnerability is known as CVE-2018-9559 since 04/05/2018. Attacking locally is a requirement. The successful exploitation requires a single authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/18/2020). It is expected to see the exploit prices for this product increasing in the near future.

The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $25k-$100k.

Applying a patch is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 106147†). The entries VDB-127674, VDB-127675, VDB-127676 and VDB-127677 are pretty similar. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Smartphone Operating System

Vendor

• Google

Name

• Android

Version

• 7.0
• 7.1.1
• 7.1.2
• 8.0
• 8.1

License

• free

Website

• Vendor: https://www.google.com/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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

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