EspoCRM, an open source CRM, contains an ACL bypass that allows a portal user with stream access to directly fetch a Note via the portal Note API when the note ID is known. The API fails to enforce the isInternal visibility filter and exposes internal agent content. This results in confidential information leakage where portal users can read private notes that should be restricted to internal staff.

This vulnerability affects all EspoCRM installations prior to version 9.3.7. Any deployment that assigns portal roles the ability to access streams is at risk per the advisory. The issue was fixed in the 9.3.7 release.

The CVSS score of 6.5 indicates moderate severity, and the EPSS score of less than 1% shows that the likelihood of exploitation is currently very low. The advisory notes that exploitation requires an authenticated portal user who knows a specific note identifier. Because the note identifier must be known and the portal user must have stream access, the attack vector is relatively constrained. The vulnerability is not listed in the CISA KEV catalog, suggesting that no widespread exploitation has been observed.