CVE-2026-42007

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.

CVSS v3 9.1 CRITICAL

9.1^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.1 / Impact : 5.3

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0003.json

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 12:16

Updated : 2026-09-03 18:13

NVD link : CVE-2026-42007

Mitre link : CVE-2026-42007

CVE.ORG link : CVE-2026-42007

JSON object : View

Products Affected

No product.

CWE

CWE-416

Use After Free

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