A write-what-where condition in hermes caused by an integer overflow, prior to commit 5b6255ae049fa4641791e47fad994e8e8c4da374 allows attackers to potentially execute arbitrary code via crafted JavaScript. Note that this is only exploitable if the application using Hermes permits evaluation of untrusted JavaScript. Hence, most React Native applications are not affected.
The product performs a calculation to determine how much memory to allocate, but an integer overflow can occur that causes less memory to be allocated than expected, leading to a buffer overflow.
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
| Link | Tags |
|---|---|
| https://github.com/facebook/hermes/commit/5b6255ae049fa4641791e47fad994e8e8c4da374 | third party advisory patch |
| https://www.facebook.com/security/advisories/CVE-2022-35289 | vendor advisory |