CVE-2026-27858 (GCVE-0-2026-27858)
Vulnerability from cvelistv5 – Published: 2026-03-27 08:10 – Updated: 2026-03-27 12:37
VLAI?
Summary
Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory.
Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install fixed version. No publicly available exploits are known.
Severity ?
7.5 (High)
CWE
- CWE-400 - Uncontrolled Resource Consumption
Assigner
References
| URL | Tags | ||||
|---|---|---|---|---|---|
|
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Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Open-Xchange GmbH | OX Dovecot Pro |
Affected:
0 , ≤ 2.3.0
(semver)
Affected: 0 , ≤ 3.1.0 (semver) Affected: 0 , ≤ 2.4.0 (semver) |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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