Name: CVE-2026-61911: Exposure of Sensitive System Information to an Unauthorized Control Sphere
Creator: Rapid7
Published: 2026-09-09T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-61911, CWE-497, CVSS 4.3, EPSS 0.00218

An issue was discovered in Cyrus IMAP before 3.12.4. There is a Sieve mailbox existence oracle. An authenticated user could install a Sieve script that probed whether another user's private mailbox existed, or read the value of shared mailbox annotations, by observing which fileinto branch fired during LMTP delivery.

CVSS Details

CVSS 3.1 Base Score: 4.3
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Redhat_linux	—	No solution exists	Sep 11, 2026	Sep 10, 2026

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CVSS Details

Covered by Rapid7

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