Description
An unauthenticated attacker can crash the ManageSieve login process by sending a small malformed command before authenticating. If running in high-security mode (default for community releases), only the attacker's own connection is terminated. If running in high-performance mode (default for Pro releases), all connections handled by the same managesieve-login process are terminated. Repeating the attack can cause denial of service for Sieve script management. Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known.
Published: 2026-08-28
Score: 7.5 High
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

History

Fri, 28 Aug 2026 14:00:00 +0000

Type Values Removed Values Added
Title ManageSieve Service Denial of Service via Malformed Command

Fri, 28 Aug 2026 11:30:00 +0000

Type Values Removed Values Added
Description An unauthenticated attacker can crash the ManageSieve login process by sending a small malformed command before authenticating. If running in high-security mode (default for community releases), only the attacker's own connection is terminated. If running in high-performance mode (default for Pro releases), all connections handled by the same managesieve-login process are terminated. Repeating the attack can cause denial of service for Sieve script management. Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known.
Weaknesses CWE-400
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


Subscriptions

No data.

cve-icon MITRE

Status: PUBLISHED

Assigner: OX

Published:

Updated: 2026-08-28T15:55:19.368Z

Reserved: 2026-03-23T12:58:38.267Z

Link: CVE-2026-33605

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-28T12:16:27.740

Modified: 2026-08-28T12:16:27.740

Link: CVE-2026-33605

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-28T13:45:17Z

Weaknesses
  • CWE-400

    Uncontrolled Resource Consumption