OAuth Consent Phishing
What is OAuth Consent Phishing?
OAuth Consent PhishingAn identity attack that abuses the OAuth consent flow: instead of stealing a password, the attacker tricks the victim into granting their malicious app standing permissions (mail.read, files.read.all) on the victim's tenant.
OAuth consent phishing — also called 'illicit consent grant' — bypasses MFA and password security entirely by abusing legitimate identity flows. The attacker registers a third-party application in a target identity provider (Microsoft Entra ID, Google Workspace, Okta, GitHub) with broad permission scopes such as Mail.Read, Files.Read.All, or repo. They then send the victim a real OAuth authorization URL hosted on the IdP's domain ('login.microsoftonline.com', 'accounts.google.com') — TLS-pinned, MFA-honored, and bearing the IdP's branding. The victim clicks 'Accept', the IdP issues the attacker a refresh token, and the attacker can read mail, exfiltrate files, and post on the victim's behalf for as long as the consent stands, with no further authentication challenge. This was the technique behind Pawn Storm/APT28's 2016–2017 campaigns and remained the top-trending Entra ID risk in 2024–2025. Defenses include tenant policies that require admin approval for third-party apps, allowlists of pre-approved publishers, periodic revocation reviews, and user training to inspect the displayed permissions and publisher before clicking accept.
● Examples
- 01
An attacker emails a victim a calendar invite that links to a Microsoft consent URL for an app named 'Calendar Helper' requesting `Mail.ReadWrite` and `Files.Read.All`; once granted, the attacker reads the user's mailbox over the Graph API.
- 02
An Entra ID tenant policy blocks user consent to unverified publishers and requires global admin review for any scope beyond `User.Read`.
● Frequently asked questions
What is OAuth Consent Phishing?
An identity attack that abuses the OAuth consent flow: instead of stealing a password, the attacker tricks the victim into granting their malicious app standing permissions (mail.read, files.read.all) on the victim's tenant. It belongs to the Attacks & Threats category of cybersecurity.
What does OAuth Consent Phishing mean?
An identity attack that abuses the OAuth consent flow: instead of stealing a password, the attacker tricks the victim into granting their malicious app standing permissions (mail.read, files.read.all) on the victim's tenant.
How does OAuth Consent Phishing work?
OAuth consent phishing — also called 'illicit consent grant' — bypasses MFA and password security entirely by abusing legitimate identity flows. The attacker registers a third-party application in a target identity provider (Microsoft Entra ID, Google Workspace, Okta, GitHub) with broad permission scopes such as Mail.Read, Files.Read.All, or repo. They then send the victim a real OAuth authorization URL hosted on the IdP's domain ('login.microsoftonline.com', 'accounts.google.com') — TLS-pinned, MFA-honored, and bearing the IdP's branding. The victim clicks 'Accept', the IdP issues the attacker a refresh token, and the attacker can read mail, exfiltrate files, and post on the victim's behalf for as long as the consent stands, with no further authentication challenge. This was the technique behind Pawn Storm/APT28's 2016–2017 campaigns and remained the top-trending Entra ID risk in 2024–2025. Defenses include tenant policies that require admin approval for third-party apps, allowlists of pre-approved publishers, periodic revocation reviews, and user training to inspect the displayed permissions and publisher before clicking accept.
How do you defend against OAuth Consent Phishing?
Defences for OAuth Consent Phishing typically combine technical controls and operational practices, as detailed in the full definition above.
What are other names for OAuth Consent Phishing?
Common alternative names include: Illicit consent grant, Application consent attack.
● Related terms
- attacks№ 917
Phishing
A social-engineering attack in which an attacker impersonates a trusted party to trick a victim into revealing credentials, transferring money, or running malware.
- attacks№ 1191
Spear Phishing
A targeted phishing attack tailored to a specific individual or organization using personal or professional details collected in advance.
- identity-access№ 839
OAuth 2.0
An open authorization framework that lets a resource owner grant a third-party application limited, scoped access to an API without sharing credentials.
- attacks№ 1182
Social Engineering
The psychological manipulation of people into performing actions or disclosing confidential information that benefits an attacker.
- attacks№ 341
Device Code Phishing
An identity attack that abuses the OAuth 2.0 device authorization grant: the attacker starts a device-code flow and lures the victim into typing the resulting code on a legitimate login page, granting the attacker tokens for the victim's account.
- attacks№ 011
Account Takeover (ATO)
An attack in which a criminal gains unauthorised control of a legitimate user account and uses it to steal funds, data, or commit further fraud.
● See also
- № 753Microsoft Entra ID