CVE Analysis 3 min read

CVE-2026-14262: Simple JWT Login - Privilege escalation

CVE-2026-14262 CVSS 8.8 HIGH vulnerability analysis

CVE-2026-14262 is a high severity vulnerability (CVSS 8.8) identified in the National Vulnerability Database. The Simple JWT Login - Allows you to use JWT on REST endpoints. plugin for WordPress is vulnerable to Authentication Bypass to Privilege Escalation in all versions up to and including, 3.6.6 via the `payload` parameter. The vulnerability exists because `AuthenticateService::generatePayload()` only overwrites JWT payload keys

TL;DR: This is a privilege escalation vulnerability (CVSS 8.8 HIGH). Authentication: Required (authenticated). Patch immediately.

What This Vulnerability Is

The Simple JWT Login - Allows you to use JWT on REST endpoints. plugin for WordPress is vulnerable to Authentication Bypass to Privilege Escalation in all versions up to and including, 3.6.6 via the `payload` parameter. The vulnerability exists because `AuthenticateService::generatePayload()` only overwrites JWT payload keys whose names appear in the admin-configured `jwt_payload` list - leaving any attacker-supplied identity claims such as `email`, `id`, or `username` intact and signed into the JWT with the site's HS256 secret. This makes it possible for authenticated attackers, with subscriber-level access and above, to escalate their privileges to that of an Administrator by injecting a target administrator's email address into the `payload` parameter at the `/wp-json/simple-jwt-login/v1/auth` endpoint, then redeeming the resulting JWT at the `/autologin` endpoint to obtain a fully authenticated session as that administrator.

The National Vulnerability Database assigned this issue a CVSS base score of 8.8, placing it in the HIGH category. The identifier CVE-2026-14262 was published on 2026-07-11T05:16:32.367.

CVE Identifier
CVE-2026-14262
CVSS Base Score
8.8 / 10.0 (HIGH)
Published
2026-07-11T05:16:32.367
NVD Entry
https://nvd.nist.gov/vuln/detail/CVE-2026-14262
MITRE Entry
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-14262

Who Is Affected

Based on the vulnerability data published by NVD, the following products and configurations are identified as affected:

  • Specific affected products are listed in the NVD entry. Review the CPE data for your stack.

If your organization uses any of the above, this vulnerability applies to your environment. Even if your specific version is not listed, review the full CPE match data to confirm.

What Attack Traffic Looks Like

Illustrative patterns for defensive detection. Not a working exploit.

Authentication bypass attempts access protected resources without valid credentials. Watch for:

  • Admin endpoint access without session cookies or auth tokens
  • Manipulation of authentication headers (JWT tampering, cookie forgery)
  • Direct access to API endpoints that should require authentication

How to Detect It

Sigma Rule

title: Unauthenticated Access to Protected Endpoint
id: auto-cwe287-detection
status: experimental
description: Detects access to admin or authenticated endpoints without valid session identifiers.
logsource:
  category: webserver
detection:
  selection_path:
    cs-uri-stem|contains:
      - '/admin/'
      - '/api/admin'
      - '/management/'
  filter_auth:
    cs-cookie|contains: 'session'
  condition: selection_path and not filter_auth
level: high

IOC Hunt List

  • Admin actions in audit logs without corresponding authentication events
  • Multiple failed authentication attempts followed by successful access without valid login
  • Access from unusual source IPs to administrative interfaces

What to Do About It

Here is what we recommend, in order of priority:

  1. Check your exposure. Determine whether the affected software or component is present in your environment. Asset inventories and software composition analysis (SCA) tools are the fastest route.
  2. Apply the patch. If a vendor patch or updated version is available, apply it. Check the references below for vendor advisories.
  3. Mitigate if patching is not immediate. If you cannot patch right now, evaluate whether network segmentation, access control changes or configuration adjustments reduce the attack surface for this specific vulnerability.
  4. Monitor for exploitation. Check whether proof-of-concept exploit code exists. The CISA Known Exploited Vulnerabilities catalog tracks actively exploited CVEs.
  5. Document your response. Record what you checked, when you patched and what residual risk remains. This matters for compliance and for incident response if this vulnerability is exploited later.

Triage Quick Start

Run as administrator. Collect artifacts before applying patches or making changes:

# Linux/Unix systems
tar czf /tmp/triage-$(hostname)-$(date +%s).tgz \
  /var/log/syslog /var/log/auth.log /var/log/messages \
  /var/log/secure /var/log/apache2/ /var/log/nginx/ \
  /etc/passwd /etc/shadow \
  /root/.bash_history \
  /home/*/.bash_history \
  /tmp/ /var/tmp/ 2>/dev/null

# Windows systems (PowerShell)
# Compress-Archive -Path C:\Windows\System32\winevt\Logs\*,C:\inetpub\logs\* -DestinationPath C:\triage.zip

If you need help analyzing these artifacts, call Sherlock Forensics at 604.229.1994.

Why This Matters for Companies Without Security Teams

A CVSS score of 8.8 means this vulnerability is straightforward to exploit, likely to cause significant damage or both. For startups and small companies operating without a dedicated security team, vulnerabilities at this severity level represent real operational risk rather than theoretical concern.

The challenge is not awareness. Vulnerability databases are public. The challenge is triage: understanding whether a given CVE affects your specific stack and knowing what to do about it before an attacker does. If you lack the internal capacity to perform that assessment, an external review of your exposure is a concrete next step.

Sherlock Forensics provides vulnerability assessment and penetration testing for organizations that need to understand their attack surface without building a full internal security function.

References and Further Reading