CVE-2020-25817

Description

SilverStripe through 4.6.0-rc1 has an XXE Vulnerability in CSSContentParser. A developer utility meant for parsing HTML within unit tests can be vulnerable to XML External Entity (XXE) attacks. When this developer utility is misused for purposes involving external or user submitted data in custom project code, it can lead to vulnerabilities such as XSS on HTML output rendered through this custom code. This is now mitigated by disabling external entities during parsing. (The correct CVE ID year is 2020 [CVE-2020-25817, not CVE-2021-25817]).

Category

4.8
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.35%
Vendor Advisory silverstripe.org Vendor Advisory silverstripe.org Vendor Advisory silverstripe.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://www.silverstripe.org/download/security-releases/ vendor advisory
https://www.silverstripe.org/blog/tag/release release notes vendor advisory
https://forum.silverstripe.org/c/releases release notes vendor advisory
https://www.silverstripe.org/download/security-releases/cve-2020-25817 broken link

Frequently Asked Questions

What is the severity of CVE-2020-25817?
CVE-2020-25817 has been scored as a medium severity vulnerability.
How to fix CVE-2020-25817?
To fix CVE-2020-25817, 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-2020-25817 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-25817 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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