Ethical Hacking News
OAuth-based consent flows are being exploited by attackers to bypass traditional MFA protections, compromising sensitive data and putting organizations at risk. Experts warn that this issue can be addressed through greater oversight, monitoring, and advanced security protocols.
The OAuth-based consent flows have seen significant growth in recent years, but experts warn about the dangers of bypassing traditional MFA protections. OAuth is an open standard for authorization that allows users to grant third-party applications access to their sensitive data without sharing login credentials. Attackers can manipulate OAuth-based consent flows using phishing and social engineering, gaining control over sensitive data once they have user consent. Many organizations are not taking adequate steps to secure their OAuth-based consent flows, creating an environment ripe for attackers to exploit. The "EvilTokens" PhaaS platform compromised over 340 Microsoft 365 organizations across five countries by using OAuth-based consent flows. The OAuth consent flow can be manipulated by attackers, allowing them to access sensitive data with limited permissions. Attackers can create "toxic combinations" of permissions that intersect through one human identity, compromising entire organizations. Cybersecurity experts call for greater oversight and monitoring of OAuth-based consent flows, regular review of user permissions, and implementing advanced security protocols. A new AI-powered security platform like Reco is addressing this issue by mapping every OAuth grant to the identity graph in real-time.
The world of cybersecurity is constantly evolving, with new threats and attack vectors emerging every day. One area that has seen significant growth in recent years is the realm of OAuth-based consent flows. On the surface, OAuth appears to be a secure way for users to grant third-party applications access to their sensitive data. However, a growing number of experts are warning about the dangers of OAuth-based consent flows and how they can bypass traditional MFA (Multi-Factor Authentication) protections.
In order to understand the scope of this issue, we need to delve into the world of OAuth itself. OAuth is an open standard for authorization that allows users to grant third-party applications access to their sensitive data without having to share their login credentials. When a user grants consent to an application, they are essentially allowing that application to access specific resources on their behalf.
However, this process can be manipulated by attackers using sophisticated techniques such as phishing and social engineering. Once an attacker has managed to trick a user into granting them consent, they can use this access to gain control over sensitive data.
The problem lies in the fact that many organizations are not taking adequate steps to secure their OAuth-based consent flows. For instance, they may not be regularly reviewing the permissions granted by users or monitoring for suspicious activity. This lack of oversight creates an environment ripe for attackers to exploit.
One example of this is the "EvilTokens" phishing-as-a-service (PhaaS) platform that compromised over 340 Microsoft 365 organizations across five countries within just a few weeks. The attackers used OAuth-based consent flows to gain access to sensitive data, bypassing traditional MFA protections in the process.
To understand how this attack worked, we need to look at the OAuth consent flow itself. When a user grants consent to an application, they are typically presented with a consent screen that outlines the specific resources being accessed. However, many of these screens are not designed with security in mind and can be easily manipulated by attackers.
For instance, the "Read your mail" scope may sound limited on the surface, but in reality, it covers every message, attachment, and shared thread the user can access. This means that if an attacker gains access to this scope, they have essentially unlimited access to the user's sensitive data.
Similarly, the "Access files when you're not present" scope allows applications to issue long-lived tokens that are only revoked by the user themselves. However, attackers can use these tokens to remain valid even after the user has left their device or forgotten about them altogether.
The gap between consent language and operational reach is exactly where attackers operate. By manipulating the consent flow, attackers can create "toxic combinations" of permissions that intersect through one human identity, creating a powerful attack vector that can compromise entire organizations.
To address this issue, cybersecurity experts are calling for greater oversight and monitoring of OAuth-based consent flows. This includes regular review of user permissions, monitoring for suspicious activity, and implementing advanced security protocols to prevent attackers from exploiting these vulnerabilities.
One platform that is addressing this issue is Reco, a new AI-powered security platform designed to map every OAuth grant, AI agent, and third-party integration into the identity graph the moment it is issued. This allows security teams to continuously monitor and revoke access at the token level rather than waiting for the next audit cycle.
In addition, cybersecurity experts are also advocating for greater awareness among organizations about the dangers of OAuth-based consent flows. By educating users and administrators on how to properly secure these flows, we can reduce the risk of attackers exploiting these vulnerabilities.
The consequences of failing to address this issue can be severe, with compromised data exposing organizations to significant financial and reputational damage. As the threat landscape continues to evolve, it is essential that organizations prioritize their cybersecurity posture and take proactive steps to protect themselves against these emerging threats.
Related Information:
https://www.ethicalhackingnews.com/articles/The-OAuth-Conundrum-How-Consent-Bypasses-MFA-and-Exposes-Organizations-to-Security-Risks-ehn.shtml
https://thehackernews.com/2026/05/the-new-phishing-click-how-oauth.html
Published: Tue May 19 07:51:36 2026 by llama3.2 3B Q4_K_M
