CVE-2021-23437: Regular Expression Denial of Service (ReDoS)

Published Sep 3, 2021
·
Updated

The package pillow 5.2.0 and before 8.3.2 are vulnerable to Regular Expression Denial of Service (ReDoS) via the getrgb function.

Affected Software

4 affected componentsFixes available
pip/pillow>=5.2.0<8.3.2
8.3.2
Python Pillow>=5.2.0<8.3.2
Fedoraproject Fedora=33
Fedoraproject Fedora=34

Event History

Sep 3, 2021
CVE Published
via MITRE·04:10 PM
Data Sourced
via MITRE·04:10 PM
DescriptionSeverityWeakness
Sep 7, 2021
Advisory Published
via GitHub·11:08 PM
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Frequently Asked Questions

1

What is vulnerability CVE-2021-23437?

Vulnerability CVE-2021-23437 is a Regular Expression Denial of Service (ReDoS) vulnerability in the package pillow version 5.2.0 and before 8.3.2.

2

How does the vulnerability CVE-2021-23437 impact the affected software?

The vulnerability CVE-2021-23437 allows an attacker to perform a Regular Expression Denial of Service (ReDoS) attack via the getrgb function in the pillow package.

3

What is the severity level of vulnerability CVE-2021-23437?

The severity level of vulnerability CVE-2021-23437 is high, with a severity value of 7.5.

4

How can I fix vulnerability CVE-2021-23437?

To fix vulnerability CVE-2021-23437, update the pillow package to version 8.3.2 or above.

5

Where can I find more information about vulnerability CVE-2021-23437?

You can find more information about vulnerability CVE-2021-23437 at the following references: [NVD](https://nvd.nist.gov/vuln/detail/CVE-2021-23437), [GitHub](https://github.com/python-pillow/Pillow/commit/9e08eb8f78fdfd2f476e1b20b7cf38683754866b), [Pillow Release Notes](https://pillow.readthedocs.io/en/stable/releasenotes/8.3.2.html).

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