CVE-2026-27858
Last modified
CVE-2026-27858 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 0.79% chance of exploitation in the next 30 days.
Description
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Dovecot | Dovecot | < 2.4.3 |
| Open-Xchange | Dovecot | < 2.3.22.1 |
| Open-Xchange | Dovecot | >= 3.0.0, < 3.0.5 |
| Open-Xchange | Dovecot | >= 3.1.0, < 3.1.4 |
References
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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