CVE-2020-1921: High severity facebook hiphop virtual machine vulnerability

Published Mar 10, 2021
·
Updated

In the crypt function, we attempt to null terminate a buffer using the size of the input salt without validating that the offset is within the buffer. 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.

Affected Software

8 affected components
Facebook HHVM<4.56.3
Facebook HHVM>=4.57.0<4.80.2
Facebook HHVM>=4.81.0<4.93.2
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

Event History

Mar 10, 2021
CVE Published
via MITRE·03:50 PM
Data Sourced
via MITRE·03:50 PM
DescriptionWeakness
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Frequently Asked Questions

1

What is CVE-2020-1921?

CVE-2020-1921 is a vulnerability in the crypt function of 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.

2

How does CVE-2020-1921 affect HHVM?

CVE-2020-1921 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. It does not affect versions 4.95.0, 4.96.0, 4.97.0, and 4.98.0.

3

What is the severity of CVE-2020-1921?

CVE-2020-1921 has a severity rating of 7.5 (high).

4

How can I fix CVE-2020-1921?

To fix CVE-2020-1921, update your HHVM to version 4.56.3 or later, 4.80.2 or later, 4.93.2 or later, or 4.94.0 if you are using that specific version.

5

Where can I find more information about CVE-2020-1921?

You can find more information about CVE-2020-1921 on the GitHub commit page (https://github.com/facebook/hhvm/commit/08193b7f0cd3910256e00d599f0f3eb2519c44ca) and the HHVM blog post (https://hhvm.com/blog/2021/02/25/security-update.html).

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