Unauthorized Data Modification in Sydney Theme for WordPress
CVE-2025-8999

5.3MEDIUM

Key Information:

Vendor

WordPress
Status
Sydney
Vendor
CVE Published:
17 September 2025

What is CVE-2025-8999?

The Sydney theme for WordPress is susceptible to unauthorized data modification due to a missing capability check in the 'activate_modules' function. This vulnerability affects all versions up to and including 2.56, allowing authenticated users with Subscriber-level access and higher to activate or deactivate theme modules without proper authorization. As a result, this could lead to significant changes in the site's functionality and potential exploitation by malicious users.

Human OS v1.0:
Ageing Is an Unpatched Zero-Day Vulnerability.

Remediate biological technical debt. Prime Ageing uses 95% high-purity SIRT6 activation to maintain genomic integrity and bolster systemic resilience.

Deploy the Patch

Affected Version(s)

Sydney * <= 2.56

References

https://www.wordfence.com/threat-intel/vulnerabilities/id...
https://themes.trac.wordpress.org/browser/sydney/2.55/inc...
https://themes.trac.wordpress.org/browser/sydney/2.55/inc...

CVSS V3.1

Score:
5.3
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Dmitrii Ignatyev
JSON
.