CVE-2026-33605 (GCVE-0-2026-33605)
Vulnerability from cvelistv5 – Published: 2026-08-28 10:12 – Updated: 2026-08-28 15:55
VLAI
EPSS
VEX
Summary
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.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 14:42 UTC
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://documentation.open-xchange.com/dovecot/se… | vendor-advisory |
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Open-Xchange GmbH | OX Dovecot Pro |
Affected:
2.3.0 , < 2.3.22.2
(semver)
Affected: 3.0.0 , < 3.0.7 (semver) Affected: 3.1.0 , < 3.1.6 (semver) |
guessed | |
| Open-Xchange GmbH | OX Dovecot CE |
Affected:
2.3.0 , < 2.4.5
(semver)
|
guessed |
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| Author | Source | Type | Date | Other |
|---|
Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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