Description
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.
Published: 2026-09-09
Score: 4.3 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

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Advisories

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History

Wed, 09 Sep 2026 20:15:00 +0000

Type Values Removed Values Added
First Time appeared Cyrusimap
Cyrusimap cyrus Imap
Weaknesses CWE-497
CPEs cpe:2.3:a:cyrusimap:cyrus_imap:*:*:*:*:*:*:*:*
Vendors & Products Cyrusimap
Cyrusimap cyrus Imap
Metrics cvssV3_1

{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'}

Wed, 09 Sep 2026 20:00:00 +0000

Type Values Removed Values Added
Description 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.
References

Subscriptions

Cyrusimap Cyrus Imap
cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2026-09-09T19:59:30.468Z

Reserved: 2026-07-13T00:00:00.000Z

Link: CVE-2026-61911

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-09-09T20:18:36.800

Modified: 2026-09-09T20:22:32.663

Link: CVE-2026-61911

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses
  • CWE-497

    Exposure of Sensitive System Information to an Unauthorized Control Sphere