CVE-2021-24025: facebook hhvm Heap-based Buffer Overflow

Vulnerability summary

CVE-2021-24025 is a critical (CVSS 9.8) Heap-based Buffer Overflow vulnerability in facebook hhvm. EPSS estimates a 1.66% chance of exploitation in the next 30 days, higher than 76.3% of scored vulnerabilities.

Timeline

1. 10-03-2021
   PublishedVulnerability first disclosed.
2. 03-08-2024
   Last modifiedVulnerability information updated.

Description

Due to incorrect string size calculations inside the preg_quote function, a large input string passed to the function can trigger an integer overflow leading to a heap overflow. This issue affects HHVM versions prior to 4.56.3, all versions between 4.57.0 and 4.80.1, all versions between 4.81.0 and 4.93.1, and versions 4.94.0, 4.95.0, 4.96.0, 4.97.0, 4.98.0.

• CWE-122Heap-based Buffer OverflowA heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().
• CWE-190Integer Overflow or WraparoundThe 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.