CVE-2021-3838

Public Exploit
PHAR Deserialization in dompdf/dompdf

Description

DomPDF before version 2.0.0 is vulnerable to PHAR deserialization due to a lack of checking on the protocol before passing it into the file_get_contents() function. An attacker who can upload files of any type to the server can pass in the phar:// protocol to unserialize the uploaded file and instantiate arbitrary PHP objects. This can lead to remote code execution, especially when DOMPdf is used with frameworks with documented POP chains like Laravel or vulnerable developer code.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 3.0 •
EPSS 5.35% Top 15%
Third-Party Advisory huntr.com
Affected: dompdf dompdf/dompdf
Published at:
Updated at:

References

Link Tags
https://huntr.com/bounties/0bdddc12-ff67-4815-ab9f-6011a974f48e third party advisory patch issue tracking exploit
https://github.com/dompdf/dompdf/commit/99aeec1efec9213e87098d42eb09439e7ee0bb6a patch

Frequently Asked Questions

What is the severity of CVE-2021-3838?
CVE-2021-3838 has been scored as a critical severity vulnerability.
How to fix CVE-2021-3838?
To fix CVE-2021-3838, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-3838 being actively exploited in the wild?
It is possible that CVE-2021-3838 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~5% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3838?
CVE-2021-3838 affects dompdf dompdf/dompdf.
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