SilverStripe XXE Vulnerability in CSSContentParser
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]).
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Composer package | silverstripe/framework | >= 4.0.0, < 4.7.4 | 4.7.4 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2020-25817
- https://forum.silverstripe.org/c/releases
- https://github.com/silverstripe/silverstripe-framework
- https://www.silverstripe.org/blog/tag/release
- https://www.silverstripe.org/download/security-releases
- https://www.silverstripe.org/download/security-releases/cve-2021-25817
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N- Weakness (CWE)
CWE-611- Platform
- Composer
- Package
silverstripe/framework- Disclosed
- 24.05.2022
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-3vjc-5x79-m9r8 - CC BY 4.0
Vulnerability history: silverstripe/framework
All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 93
- First → latest
- 11.2019 08.2026
- Without a fix
- 1
- Exploited in attacks
- 0
Severity breakdown
- Critical 3
- High 13
- Medium 69
- Low 8
Disclosures per year
- 2019: 5
- 2020: 2
- 2021: 0
- 2022: 23
- 2023: 3
- 2024: 53
- 2025: 6
- 2026: 1
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SilverStripe XXE Vulnerability in CSSContentParser this entry
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