CVE-2026-33607
Description
A flaw was found in Dovecot. An authenticated attacker can exploit a vulnerability in the IMAP LIST command to consume excessive CPU resources. This can lead to a degradation of service or a complete denial of service (DoS) for the IMAP server, impacting the availability of email services.
Mitigation
To mitigate this issue, restrict access to the Dovecot IMAP service to trusted networks or localhost using firewall rules or Dovecot's configuration. Additionally, implement system monitoring for abnormal CPU utilization by Dovecot processes to detect and respond to potential exploitation attempts. If network configuration changes are applied, a restart of the Dovecot service may be required.
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 | None | N/A | None |
| Integrity Impact | None | N/A | None |
| 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:N/A:L
cve.org: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU)
Frequently Asked Questions
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