CVE-2023-30777
Published: 10 May 2023
Summary
CVE-2023-30777 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Advancedcustomfields Advanced Custom Fields. Its CVSS base score is 7.1 (High).
Operationally, ranked in the top 0.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
Deeper analysis
CVE-2023-30777 is an unauthenticated reflected cross-site scripting vulnerability affecting the WP Engine Advanced Custom Fields and Advanced Custom Fields Pro plugins for WordPress in versions up to and including 6.1.5. The flaw, tracked under CWE-79, carries a CVSS 3.1 score of 7.1 and permits script injection through unsanitized reflected input.
An attacker can exploit the issue by crafting a malicious link or request that is processed by an affected site; when an authenticated user follows the link, attacker-controlled JavaScript executes in the user's browser context with the site's origin. Successful exploitation can lead to theft of session tokens, administrative actions performed on behalf of the victim, or other client-side impacts without requiring prior authentication on the target site.
Advisories published by Patchstack note that the vulnerability impacts more than two million sites and recommend updating the plugins to a fixed release beyond version 6.1.5. The current EPSS score of 0.8643, with a recorded peak of 0.8732, indicates sustained exploitation interest following disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-35139
Vulnerability details
Unauth. Reflected Cross-Site Scripting (XSS) vulnerability in WP Engine Advanced Custom Fields Pro, WP Engine Advanced Custom Fields plugins <= 6.1.5 versions.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.
Validates web inputs to reject script-related content that could produce XSS.
Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.