CVE-2025-36936

Technical Details

The vulnerability resides in the `GetTachyonCommand` function within the `tachyon_server_common.h` file of the Android operating system. An integer overflow can occur when calculating the size or offset used in memory operations within this function. Specifically, if the input values used in the calculation are sufficiently large, the resulting integer value can wrap around to a small or negative value. This can lead to an out-of-bounds write when the wrapped value is used as an index or offset into a memory buffer. The out-of-bounds write allows an attacker to overwrite arbitrary memory locations, potentially corrupting data structures or injecting malicious code. The `GetTachyonCommand` function is likely involved in handling commands related to the Tachyon file system, a distributed file system used in Android. The vulnerability is triggered when processing a specially crafted command that causes the integer overflow. Due to the nature of the vulnerability, it can be exploited locally without requiring network access. The lack of required user interaction makes it particularly dangerous, as an attacker can potentially exploit it without the user's knowledge or consent. The vulnerability exists because the code does not properly validate the input values used in the calculation, allowing an attacker to manipulate these values to trigger the overflow.

The root cause is the absence of sufficient bounds checking on the input parameters to `GetTachyonCommand`. Without proper validation, an attacker can supply values that, when processed, result in an integer overflow. This overflow then leads to an incorrect memory address calculation, ultimately causing the out-of-bounds write.