CVE-2020-1917 Information

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

https://github.com/facebook/hhvm/commit/08193b7f0cd3910256e00d599f0f3eb2519c44ca https://hhvm.com/blog/2021/02/25/security-update.html

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

9.8