CVE-2026-3296
CWE-502Published: April 8, 2026· Updated: Apr 8, 2026
Official Description
The Everest Forms plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 3.4.3 via deserialization of untrusted input from form entry metadata. This is due to the html-admin-page-entries-view.php file calling PHP's native unserialize() on stored entry meta values without passing the allowed_classes parameter. This makes it possible for unauthenticated attackers to inject a serialized PHP object payload through any public Everest Forms form field. The payload survives sanitize_text_field() sanitization (serialization control characters are not stripped) and is stored in the wp_evf_entrymeta database table. When an administrator views entries or views an individual entry, the unsafe unserialize() call processes the stored data without class restrictions.
Technical Analysis
CVE-2026-3296 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.
CISA has added CVE-2026-3296 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
From a weakness classification perspective (CWE-502): Insecure deserialization vulnerabilities allow attackers to inject malicious objects during deserialization, potentially enabling remote code execution.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
News & Research Mentioning CVE-2026-3296
View CSAF Summary Successful exploitation of these vulnerabilities could allow an attacker to execute arbitrary code, cause a denial-of-service, or configuration information may be altered without authentication. The following versions of Silex Technology SD-330AC and AMC Manager are affected: SD-330AC <=1.42 (CVE-2026-32955, CVE-2026-32956, CVE-2026-32957, CVE-2026-32958, CVE-2015-5621, CVE-2026-32959, CVE-2026-32960, CVE-2026-32961, CVE-2026-32962, CVE-2024-24487, CVE-2026-32963, CVE-2026-32964, CVE-2026-32965) AMC Manager <=5.0.2 (CVE-2026-32955, CVE-2026-32956, CVE-2026-32957, CVE-2026-32958, CVE-2015-5621, CVE-2026-32959, CVE-2026-32960, CVE-2026-32961, CVE-2026-32962, CVE-2024-24487, CVE-2026-32963, CVE-2026-32964, CVE-2026-32965) CVSS Vendor E [xlite_meta score:69 src:CISA Alerts xlite_fp:59008822000cc265cfbef4a5ceb2ad1508e5d38b9789d70505eaaa38dd228d03]
All References (6)
Quick Facts
Related CVEs (CWE-502)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-3296 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1