CVE-2026-61911

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 v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://cyrusimap.org
https://www.cyrusimap.org/3.12/imap/download/release-notes/3.10/x/3.10.4.html
https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.4.html
https://www.cyrusimap.org/3.12/imap/download/release-notes/3.8/x/3.8.8.html

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-09 20:18

Updated : 2026-09-10 19:17

NVD link : CVE-2026-61911

Mitre link : CVE-2026-61911

CVE.ORG link : CVE-2026-61911

JSON object : View

Products Affected

No product.

CWE

CWE-497

Exposure of Sensitive System Information to an Unauthorized Control Sphere

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