Security readout for executives and security teams
Plain-English summary
This is a critical WordPress plugin issue in Newsletter Manager up to version 1.5.1. A public website using the affected plugin may let an unauthenticated attacker submit data that PHP deserializes unsafely. The CVSS rating is 9.8 because confidentiality, integrity, and availability impacts are all rated high.
Executive priority
Treat as urgent for any public WordPress property using this plugin. The issue is unauthenticated, network-reachable, and critical-rated. If the plugin is present and affected, removal or disablement is the safest immediate business action unless a trusted fixed version is confirmed.
Technical view
The issue is CWE-502 insecure deserialization. Unsanitized input from the customFieldsDetails parameter is passed to a deserialization function, potentially allowing unauthenticated serialized PHP object injection. Practical impact depends on reachable code paths and available PHP object behavior, but the published CVSS vector is network-accessible, low-complexity, no privileges, and no user interaction.
Likely exposure
Exposure is most likely on internet-facing WordPress sites running the Newsletter Manager plugin version 1.5.1 or earlier. The provided affected metadata is incomplete and internally inconsistent, so validation should rely on installed plugin inventory and vendor or WordPress plugin records.
Exploitation context
The source bundle does not include CISA KEV listing or cited evidence of active exploitation. It supports unauthenticated exploitability in principle, but does not prove real-world exploitation, public weaponization, or a confirmed patch level.
Researcher notes
The central evidence is the unsafe deserialization of customFieldsDetails in Newsletter Manager through version 1.5.1. The bundle does not establish active exploitation, a CISA KEV entry, or a definitive fixed release. The affected-version metadata conflict should be called out in any advisory or scanner rule.
Mitigation direction
- Identify all WordPress sites running Newsletter Manager.
- Disable or remove the plugin if business use is not essential.
- Check vendor, WordPress plugin, Wordfence, and WPScan guidance for fixed versions.
- If no fixed version exists, keep the plugin disabled until vendor guidance changes.
- Review web application logs for suspicious Newsletter Manager form activity.
Validation and detection
- Inventory WordPress plugins and confirm Newsletter Manager version on every site.
- Flag any installation at version 1.5.1 or earlier.
- Confirm whether the customFieldsDetails handling path is reachable on public pages.
- Check security tooling for Wordfence or WPScan detections tied to this CVE.
- Review logs without replaying payloads or testing deserialization behavior offensively.
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-2020-36727 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
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/dcfd8c4d-d48b-468d-a7d5-1ec05b068f79?source=cveCVE reference
- https://blog.nintechnet.com/insecure-deserialization-vulnerability-in-wordpress-newsletter-manager-plugin-unpatched/CVE reference
- https://wpscan.com/vulnerability/b82124b1-e5e1-4f1e-9513-90474fd3f066CVE reference
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.