CVE-2021-3902

Public Exploit
Improper Restriction of XML External Entity Reference in dompdf/dompdf

Description

An improper restriction of external entities (XXE) vulnerability in dompdf/dompdf's SVG parser allows for Server-Side Request Forgery (SSRF) and deserialization attacks. This issue affects all versions prior to 2.0.0. The vulnerability can be exploited even if the isRemoteEnabled option is set to false. It allows attackers to perform SSRF, disclose internal image files, and cause PHAR deserialization attacks.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 3.0 •
EPSS 2.73% Top 15%
Third-Party Advisory huntr.com
Affected: dompdf dompdf/dompdf
Published at:
Updated at:

References

Link Tags
https://huntr.com/bounties/a6071c07-806f-429a-8656-a4742e4191b1 third party advisory patch issue tracking exploit
https://github.com/dompdf/dompdf/commit/f56bc8e40be6c0ae0825e6c7396f4db80620b799 patch

Frequently Asked Questions

What is the severity of CVE-2021-3902?
CVE-2021-3902 has been scored as a critical severity vulnerability.
How to fix CVE-2021-3902?
To fix CVE-2021-3902, 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-2021-3902 being actively exploited in the wild?
It is possible that CVE-2021-3902 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~3% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3902?
CVE-2021-3902 affects dompdf dompdf/dompdf.
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