CVE-2020-1917

CRITICAL

HHVM < 4.56.3, 4.57.0-4.80.1, 4.81.0-4.93.1, 4.94.0-4.98.0 - Heap-based Buffer Overflow

Title source: llm
STIX 2.1

Description

xbuf_format_converter, used as part of exif_read_data, was appending a terminating null character to the generated string, but was not using its standard append char function. As a result, if the buffer was full, it would result in an out-of-bounds write. 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.

References (2)

Core 2
Core References
Release Notes, Vendor Advisory x_refsource_misc
https://hhvm.com/blog/2021/02/25/security-update.html

Scores

CVSS v3 9.8
EPSS 0.0138
EPSS Percentile 68.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-122 CWE-787
Status published
Products (6)
facebook/hhvm 4.94.0
facebook/hhvm 4.95.0
facebook/hhvm 4.96.0
facebook/hhvm 4.97.0
facebook/hhvm 4.98.0
facebook/hhvm < 4.56.3
Published Mar 10, 2021
Tracked Since Feb 18, 2026