CVE-2021-27921 Pillow Denial of Service by Uncontrolled Resource Consumption

What is CVE-2021-27921?

CVE-2021-27921 is a high-severity denial of service vulnerability in Fedoraproject Fedora, published on 3 Mar 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Pillow before 8.1.2 allows attackers to cause a denial of service (memory consumption) because the reported size of a contained image is not properly checked for a BLP container, and thus an attempted memory allocation can be very large.

Weakness: CWE-20

Which versions are affected by CVE-2021-27921?

4 open source packages ship an affected version, including pillow and Pillow. It affects 2 products.

Products include Fedoraproject Fedora, Python Pillow.

How do I fix CVE-2021-27921?

Upgrade pillow to a fixed version for your release line: 8.1.1 or 8.1.2.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-27921 being exploited?

There is no known exploitation of CVE-2021-27921 in the wild and no public exploit code.

Other vulnerabilities in Fedoraproject Fedora

• CVE-2024-4577 PHP-CGI OS Command Injection Exploited Critical 9.8
• CVE-2021-39226 Grafana Authentication Bypass Exploited Critical 9.8
• CVE-2019-5544 VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow Exploited Critical 9.8
• CVE-2024-4947 Google Chromium V8 Type Confusion Exploited Critical 9.6
• CVE-2024-4671 Google Chromium Visuals Use-After-Free Exploited Critical 9.6

All Fedoraproject Fedora vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2021-27921, BIT-pillow-2021-27921, DEBIAN-CVE-2021-27921, GHSA-f4w8-cv6p-x6r5, PYSEC-2021-40, ROOT-APP-PYPI-CVE-2021-27921 and 1 more.