CVE-2026-47089
Description
A flaw was found in Cyrus IMAP (cyrus-imapd). An authenticated user can exploit this vulnerability by using the IMAP LISTRIGHTS command. This allows the user to learn the access permissions of any mailbox they can name, which should be restricted to administrators. This leads to unauthorized information disclosure regarding mailbox access controls.
Statement
This Moderate-impact information disclosure flaw in Cyrus IMAP allows an authenticated user to enumerate mailbox access rights via the LISTRIGHTS command. While requiring prior authentication, this bypasses intended administrative restrictions, potentially exposing sensitive access control configurations within a Red Hat deployment. The impact is limited to information disclosure and does not grant further privileges or data modification.
Mitigation
To mitigate this issue, restrict network access to the Cyrus IMAP service to only trusted clients and networks. This can be achieved by configuring firewall rules to limit inbound connections to the IMAP port (typically 143 for IMAP and 993 for IMAPS) on the server hosting cyrus-imapd. Additionally, ensure that only necessary users have authenticated access to the IMAP server.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.3 | N/A | 4.3 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | Low | N/A | Low |
| Integrity Impact | None | N/A | None |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Understanding the Weakness (CWE)
Access Control
Technical Impact: Gain Privileges or Assume Identity
A user can access restricted functionality and/or sensitive information that may include administrative functionality and user accounts.
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