Security readout for executives and security teams
Plain-English summary
CVE-2025-54001 is a critical vulnerability in the WordPress Classter theme from ThemeREX, affecting versions through 2.5. A remote unauthenticated attacker may be able to abuse unsafe data deserialization, potentially leading to full site compromise. No active exploitation is confirmed in the provided sources.
Executive priority
Treat this as urgent for any WordPress site running Classter. The vulnerability has maximum-impact characteristics and requires no login per CVSS, but business urgency depends on whether the theme is present in your environment.
Technical view
The issue is CWE-502, deserialization of untrusted data, allowing PHP object injection in ThemeREX Classter theme <=2.5. The CVSS 3.1 score is 9.8 with network access, low complexity, no privileges, and no user interaction required, with high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is limited to WordPress sites using the ThemeREX Classter theme at version 2.5 or earlier. The sources do not identify affected plugins, other ThemeREX products, hosting platforms, or a patched version.
Exploitation context
The CVSS vector indicates remote, unauthenticated exploitation may be possible without user interaction. However, the provided sources do not confirm public exploit code, in-the-wild exploitation, or CISA KEV listing.
Researcher notes
The available record is sparse. It identifies PHP object injection via unsafe deserialization in Classter <=2.5, but does not provide sink details, gadget requirements, fixed release information, or exploitation evidence. Validate exposure carefully before escalating incident response.
Mitigation direction
- Identify any WordPress sites using the Classter theme.
- If Classter is unused, remove or replace it with a maintained theme.
- If still needed, check ThemeREX and Patchstack guidance for an updated safe version.
- Prioritize backup and change control before theme replacement or updates.
Validation and detection
- Inventory WordPress themes across production, staging, and development sites.
- Confirm whether Classter is installed or active.
- Verify the installed Classter version is greater than 2.5, if a fixed version exists.
- Review Patchstack and vendor advisories for current remediation status.
- Monitor logs for suspicious unauthenticated requests, while avoiding assumptions of compromise.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-502: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2025-54001 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Deserialization of Untrusted Data
Deserialization of Untrusted Data represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.