CVE-2026-42007
CRITICAL
9,1
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: changed
Confidentiality: low
Integrity: low
Availability: high
Description
AI Translation Available
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.
416
Use After Free
StableCommon Consequences
Security Scopes Affected:
Integrity
Availability
Confidentiality
Potential Impacts:
Modify Memory
Dos: Crash, Exit, Or Restart
Read Memory
Execute Unauthorized Code Or Commands
Applicable Platforms
Languages:
Memory-Unsafe, C, C++
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/ox…