CVE-2026-42007
CVSS Score
9.1
EPSS Score
0.0%
EPSS Percentile
0th
An attacker that has valid credentials can use a Sieve script with the editheader extension to trigger a use-after-free in the mail editing code, and to write memory contents beyond the intended buffer into the delivered mail. This causes memory leak and opportunity to do memory corruption during mail delivery, which can crash the delivery process and may allow execution of arbitrary code in the context of that process. Disable the Sieve editheader extension. Update to non-vulnerable version. No publicly available exploits are known.
| CWE | CWE-416 |
| Vendor | open-xchange gmbh |
| Product | ox dovecot pro |
| Published | Aug 28, 2026 |
| Last Updated | Aug 28, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
High
Affected Versions
Open-Xchange GmbH / OX Dovecot Pro
2.3.0 < 2.3.22.2 3.0.0 < 3.0.7 3.1.0 < 3.1.6
Open-Xchange GmbH / OX Dovecot CE
2.3.0 < 2.4.5