CVE-2026-47082
Description
A flaw was found in Cyrus IMAP's cyrus-imapd component. A user with low privileges can exploit a vulnerability in the vacation "fcc" feature. By crafting a specific Sieve script, the user can bypass access control lists and deliver vacation auto-reply messages into any mailbox, leading to unauthorized modification of mailbox content.
Statement
This Moderate impact flaw in Cyrus IMAP allows a low-privileged user to bypass access control lists via a crafted Sieve script utilizing the vacation 'fcc' feature. This enables unauthorized delivery of vacation auto-reply messages into arbitrary mailboxes, leading to modification of mailbox content.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
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 | 5.4 | N/A | 5.4 |
| 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 | None | N/A | None |
| Integrity Impact | Low | N/A | Low |
| Availability Impact | Low | N/A | Low |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
cve.org: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
Understanding the Weakness (CWE)
Confidentiality,Integrity
Technical Impact: Read Application Data; Modify Application Data
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