Product Overview

Ghost CMS is an open-source publishing and newsletter platform widely used for blogs, media sites, and subscription-based content. It supports role-based access (Owner, Administrator, Editor, Author, Contributor), staff authentication, API-based integrations, and email-based two-factor authentication (2FA) for sensitive accounts.

Because Ghost is often internet-facing and manages subscriber data, authentication and authorization flaws can have serious real-world impact.

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Initial Vulnerability Summary (Quick View)

Field	CVE-2026-22594	CVE-2026-22595
Vulnerability Type	Authentication Bypass	Authorization / Privilege Bypass
Title	Staff 2FA Bypass	Staff Token Misuse
Severity	High	High
CVSS v3 Score	8.1	8.1
Attack Vector	Network (Remote)	Network (Remote)
Privileges Required	Low (Staff account)	Low (Staff token)
User Interaction	None	None
Impact	Account takeover, unauthorized access	Unauthorized admin actions
Exploit Maturity	No public exploit (logic-based)	No public exploit (logic-based)
Patch Available	Yes	Yes

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CVE-2026-22594 — Ghost CMS Staff 2FA Bypass

What This Vulnerability Is

This vulnerability allows a staff user to successfully authenticate without completing the required email-based two-factor authentication (2FA).

Ghost uses an email-based verification step after password authentication for staff accounts. Due to a flaw in how the backend validates the authentication state, the application may incorrectly mark a login session as fully authenticated even when the 2FA confirmation step was never completed.

In short:
➡ Password-only login can be mistakenly treated as password + 2FA login

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Why This Is Dangerous

2FA is meant to stop attackers who already know or steal a password.
With this flaw:

• Phished or leaked staff credentials become immediately usable
• No email confirmation is actually required
• Attackers gain access to staff dashboards
• Content, newsletters, and site configuration can be modified
• This can be chained with other flaws to escalate further

Because Ghost staff roles can publish content and interact with members, this creates a real risk of site defacement, phishing campaigns, or data misuse.

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How This Can Be Exploited

For educational and defensive understanding only

1. An attacker obtains valid staff credentials (password reuse, phishing, malware, credential stuffing).
2. The attacker initiates the login process.
3. The backend issues a valid authenticated session before the email 2FA challenge is fully verified.
4. The attacker skips or manipulates the 2FA confirmation step.
5. The application incorrectly treats the session as authenticated.
6. The attacker gains full staff access without the second factor.

This is a logic flaw, not a brute-force or injection issue.

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Proof of Concept (Educational)

There is no publicly released exploit code.
However, from a defensive standpoint, exploitation would involve:

• Observing authentication API calls
• Replaying or modifying the login sequence
• Reusing partially validated session tokens
• Forcing session continuation without a confirmed 2FA flag

Because this does not rely on memory corruption or payload injection, it is quiet and difficult to detect without proper logging.

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Detection & Monitoring Strategy

Log Sources to Monitor

• Ghost application logs (authentication events)
• Web server or reverse proxy logs (login endpoints)
• Session issuance logs
• Email delivery logs for 2FA codes
• Admin/staff activity logs

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High-Risk Indicators

• Staff login success without a corresponding 2FA verification event
• Login success followed immediately by admin actions
• Staff login from new IP or geography with no 2FA record
• Multiple failed 2FA attempts followed by a successful session

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Detection Logic

Rule 1 – Staff session created without 2FA confirmation

IF user_role = "staff"
AND login_status = "success"
AND two_factor_verified = false
THEN alert = high

Rule 2 – Admin activity immediately after login

IF user_role = "staff"
AND login_success_time < 2 minutes
AND admin_action_detected = true
THEN alert = high

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MITRE ATT&CK Mapping

• T1078 – Valid Accounts
• T1556 – Modify Authentication Process

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Recommended Mitigation

• Immediately upgrade to a patched Ghost version
• Force logout of all staff users after patching
• Require staff to re-enroll 2FA
• Monitor authentication logs closely for anomalies

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Official Patch / Upgrade Link

https://github.com/TryGhost/Ghost/security/advisories

(Upgrade to v5.130.6, v6.11.0, or later)

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CVE-2026-22595 — Ghost CMS Staff Token Privilege Bypass

What This Vulnerability Is

Ghost provides staff tokens for integrations and automated systems.
These tokens are intended for limited, non-interactive use.

Due to an authorization flaw, these tokens could be incorrectly accepted by endpoints that should only allow authenticated staff sessions, effectively granting higher privileges than intended.

➡ A token meant for automation could behave like a logged-in staff user.

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Why This Is Dangerous

If a staff token is leaked, misconfigured, or abused:

• Admin-only endpoints can be accessed
• Content can be modified or deleted
• Member data may be exposed
• Actions appear legitimate in logs

This is especially dangerous because API tokens are often shared with third-party services.

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How This Can Be Exploited

Educational explanation only

1. An attacker gains access to a staff token (leak, misconfiguration, compromised integration).
2. The attacker sends requests to admin-only Ghost API endpoints.
3. Due to improper authorization checks, the backend validates the token incorrectly.
4. The request is processed as if it came from a logged-in staff user.
5. Unauthorized administrative actions are executed.

This is not brute-force or injection-based; it is a permission validation failure.

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Proof of Concept (Educational)

No public exploit exists.
A theoretical PoC would:

• Use a valid staff token in the Authorization header
• Call endpoints intended only for staff sessions
• Successfully perform actions without interactive login

This makes detection harder because the request structure looks legitimate.

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Detection & Monitoring Strategy

Log Sources to Monitor

• API access logs
• Authorization header parsing logs
• Token issuance and rotation logs
• Reverse proxy logs
• Audit trails for content and configuration changes

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High-Risk Indicators

• Admin endpoints accessed using API tokens
• Token usage from unexpected IP addresses
• Non-interactive tokens performing interactive actions
• Large numbers of changes from integration accounts

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Detection Logic

Rule 1 – Token accessing admin endpoints

IF token_type = "staff"
AND request_path CONTAINS "/admin/"
THEN alert = high

Rule 2 – Token activity from new source

IF token_used = true
AND source_ip NOT IN known_ranges
THEN alert = medium

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MITRE ATT&CK Mapping

• T1078 – Valid Accounts
• T1068 – Privilege Escalation
• T1550 – Use of Application Access Tokens

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Recommended Mitigation

• Rotate all staff and integration tokens
• Review all active integrations
• Apply patched Ghost version immediately
• Restrict API token usage by IP where possible
• Monitor admin API access continuously

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Official Patch / Upgrade Link

https://github.com/TryGhost/Ghost/security/advisories

(Upgrade to v5.130.6, v6.11.0, or later)

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Final Takeaway

Both vulnerabilities are logic flaws, not noisy attacks.
They will not trigger traditional IDS signatures.

If Ghost is internet-facing and staff accounts exist:

• Patch immediately
• Rotate credentials and tokens
• Audit recent staff activity
• Treat unexplained admin actions as potential compromise

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