Mastodon prior 3.5.18/4.0.14/4.1.14/4.2.6 Email Address improper authentication

Summaryinfo

A vulnerability labeled as critical has been found in Mastodon. This impacts an unknown function of the component Email Address Handler. Executing a manipulation can lead to improper authentication. This vulnerability is registered as CVE-2024-25618. It is possible to launch the attack remotely. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical was found in Mastodon. This vulnerability affects an unknown part of the component Email Address Handler. The manipulation with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Mastodon is a free, open-source social network server based on ActivityPub. Mastodon allows new identities from configured authentication providers (CAS, SAML, OIDC) to attach to existing local users with the same e-mail address. This results in a possible account takeover if the authentication provider allows changing the e-mail address or multiple authentication providers are configured. When a user logs in through an external authentication provider for the first time, Mastodon checks the e-mail address passed by the provider to find an existing account. However, using the e-mail address alone means that if the authentication provider allows changing the e-mail address of an account, the Mastodon account can immediately be hijacked. All users logging in through external authentication providers are affected. The severity is medium, as it also requires the external authentication provider to misbehave. However, some well-known OIDC providers (like Microsoft Azure) make it very easy to accidentally allow unverified e-mail changes. Moreover, OpenID Connect also allows dynamic client registration. This issue has been addressed in versions 4.2.6, 4.1.14, 4.0.14, and 3.5.18. Users are advised to upgrade. There are no known workarounds for this vulnerability.

The weakness was published 02/15/2024 as GHSA-vm39-j3vx-pch3. The advisory is shared for download at github.com. This vulnerability was named CVE-2024-25618 since 02/08/2024. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

Upgrading to version 3.5.18, 4.0.14, 4.1.14 or 4.2.6 eliminates this vulnerability. Applying the patch b31af34c9716338e4a32a62cc812d1ca59e88d15 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

• Mastodon

License

• open-source

Website

• Product: https://github.com/mastodon/mastodon/

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Once again VulDB remains the best source for vulnerability data.

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