Insufficient boundary checks when formatting numbers in number_format allows read/write access to out-of-bounds memory, potentially leading to remote code execution. This issue affects HHVM versions prior to 3.30.10, all versions between 4.0.0 and 4.8.5, all versions between 4.9.0 and 4.18.2, and versions 4.19.0, 4.19.1, 4.20.0, 4.20.1, 4.20.2, 4.21.0, 4.22.0, 4.23.0.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
| Link | Tags |
|---|---|
| https://github.com/facebook/hhvm/commit/dbeb9a56a638e3fdcef8b691c2a2967132dae692 | third party advisory patch |
| https://hhvm.com/blog/2019/09/25/security-update.html | vendor advisory |
| https://www.facebook.com/security/advisories/cve-2019-11929 | third party advisory |