PT-2026-28366 · Dovecot+4 · Dovecot+4

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CVE-2026-27858

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Published

2026-01-01

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Updated

2026-07-07

CVSS v2.0

7.8

High

VectorAV:N/AC:L/Au:N/C:N/I:N/A:C
Name of the Vulnerable Software and Affected Versions Dovecot versions prior to 2.4.3
Description An attacker can send a crafted message before authentication, leading to excessive memory allocation within the managesieve component. This can cause the managesieve-login process to crash, potentially resulting in a denial-of-service condition. No publicly available exploits are currently known.
Recommendations Update to version 2.4.3 or later. Protect access to the managesieve protocol.

Exploit

Fix

DoS

Allocation of Resources Without Limits

Resource Exhaustion

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Weakness Enumeration

Related Identifiers

ALSA-2026:13498
ALSA-2026:13830
ALSA-2026:13857
ALSA-2026:19149
ALSA-2026:19364
AZL-81710
BDU:2026-10384
CVE-2026-27858
OESA-2026-1849
OPENSUSE-SU-2026:10442-1
OPENSUSE-SU-2026:20554-1
RHSA-2026:13498
RHSA-2026:13830
RHSA-2026:13857
SUSE-SU-2026:1641-1
SUSE-SU-2026:21208-1
USN-8136-1

Affected Products

Dovecot
Linuxmint
Red Os
Rocky Linux
Ubuntu