vulnerability / NVI-00006445 / Revision 4
FriendsOfFlarum OAuth: Unauthenticated account takeover via unverified email trust in Discord OAuth provider
GitHub lists this reviewed advisory for fof/oauth, fof/oauth. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
9.8 critical
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
9.8 CRITICAL (3.1)
security-advisories@github.com severity; no combined Null risk score.
0.272%
FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.19599. Missing scores are unknown.
As of · FIRST EPSS
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
fof/oauth
source listed< 1.7.4
### Impact An unauthenticated account takeover vulnerability exists in `fof/oauth` when the Discord OAuth provider is enabled. Discord allows an account to use an unverified email address when its phone number has been verified. During OAuth authentication, Discord may return that email address with `"verified": false`. Affected versions of `fof/oauth` did not validate this flag and passed the email address to Flarum core as trusted via `provideTrustedEmail()`. Flarum core could then match the trusted email address to an existing user, link the attacker-controlled Discord identity to that user, and authenticate the attacker as the victim. An attacker who knows a user's email address can therefore take over the corresponding Flarum account without knowing its password or requiring any interaction from the victim. This includes administrator accounts. #### Preconditions for exploitation 1. Discord sign-in is enabled on the forum. 2. The victim has a Flarum account with a known email address. 3. The victim's email address is not already associated with a Discord account. 4. The attacker creates or configures a Discord account using the victim's email address without verifying it
fof/oauth
source listed>= 2.0.0-beta.1, < 2.0.0-beta.4
### Impact An unauthenticated account takeover vulnerability exists in `fof/oauth` when the Discord OAuth provider is enabled. Discord allows an account to use an unverified email address when its phone number has been verified. During OAuth authentication, Discord may return that email address with `"verified": false`. Affected versions of `fof/oauth` did not validate this flag and passed the email address to Flarum core as trusted via `provideTrustedEmail()`. Flarum core could then match the trusted email address to an existing user, link the attacker-controlled Discord identity to that user, and authenticate the attacker as the victim. An attacker who knows a user's email address can therefore take over the corresponding Flarum account without knowing its password or requiring any interaction from the victim. This includes administrator accounts. #### Preconditions for exploitation 1. Discord sign-in is enabled on the forum. 2. The victim has a Flarum account with a known email address. 3. The victim's email address is not already associated with a Discord account. 4. The attacker creates or configures a Discord account using the victim's email address without verifying it
fof/oauth
source listedECOSYSTEM: introduced 0; fixed 1.7.4
### Impact An unauthenticated account takeover vulnerability exists in `fof/oauth` when the Discord OAuth provider is enabled. Discord allows an account to use an unverified email address when its phone number has been verified. During OAuth authentication, Discord may return that email address with `"verified": false`. Affected versions of `fof/oauth` did not validate this flag and passed the email address to Flarum core as trusted via `provideTrustedEmail()`. Flarum core could then match the trusted email address to an existing user, link the attacker-controlled Discord identity to that user, and authenticate the attacker as the victim. An attacker who knows a user's email address can therefore take over the corresponding Flarum account without knowing its password or requiring any interaction from the victim. This includes administrator accounts. #### Preconditions for exploitation 1. Discord sign-in is enabled on the forum. 2. The victim has a Flarum account with a known email address. 3. The victim's email address is not already associated with a Discord account. 4. The attacker creates or configures a Discord account using the victim's email address without verifying it
fof/oauth
source listedECOSYSTEM: introduced 2.0.0-beta.1; fixed 2.0.0-beta.4
### Impact An unauthenticated account takeover vulnerability exists in `fof/oauth` when the Discord OAuth provider is enabled. Discord allows an account to use an unverified email address when its phone number has been verified. During OAuth authentication, Discord may return that email address with `"verified": false`. Affected versions of `fof/oauth` did not validate this flag and passed the email address to Flarum core as trusted via `provideTrustedEmail()`. Flarum core could then match the trusted email address to an existing user, link the attacker-controlled Discord identity to that user, and authenticate the attacker as the victim. An attacker who knows a user's email address can therefore take over the corresponding Flarum account without knowing its password or requiring any interaction from the victim. This includes administrator accounts. #### Preconditions for exploitation 1. Discord sign-in is enabled on the forum. 2. The victim has a Flarum account with a known email address. 3. The victim's email address is not already associated with a Discord account. 4. The attacker creates or configures a Discord account using the victim's email address without verifying it
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. FIRST EPSS
- vendor patch
The original advisory lists fixed boundaries 1.7.4 for fof/oauth. Confirm the publisher’s latest guidance.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV
- vendor patch
The original advisory lists fixed boundaries 2.0.0-beta.4 for fof/oauth. Confirm the publisher’s latest guidance.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
- NVD lastModified does not establish freshness of every associated CPE record.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-g7vj-c29h-3h5m ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
- GHSA-g7vj-c29h-3h5m ↗
GitHub Advisory Database via OSV · vendor advisory
Observed . GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.
- CVE-2026-92161 ↗
NIST National Vulnerability Database · official catalog
Observed . This product uses data from the NVD API but is not endorsed or certified by the NVD.
- CVE-2026-92161 ↗
FIRST EPSS · official catalog
Observed . FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 4 ·
Source facts changed; compare the preserved prior revision.
- Revision 3 ·
Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.
- Revision 2 ·
Source facts changed; compare the preserved prior revision.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.