CVE-2026-27197: Sentry: Improper authentication on SAML SSO process allows user identity linking

A critical vulnerability was discovered in the SAML SSO implementation of Sentry. It was reported to us via our private bug bounty program.

The vulnerability allows an attacker to take over any user account by using a malicious SAML Identity Provider and another organization on the same Sentry instance. The victim email address must be known in order to exploit this vulnerability.

For self-hosted users, you are only vulnerable if the following conditions are met:

• You have more than one organization configured (SENTRY_SINGLE_ORGANIZATION = False).
• A malicious user has existing access and permissions to modify SSO settings for another organization in your multo-organization instance.