CVE-2026-42007

Summary

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.

Affected Software

VendorProductVersion RangeStatus
Open-Xchange GmbHOX Dovecot Pro2.3.0 < 2.3.22.2affected
Open-Xchange GmbHOX Dovecot Pro3.0.0 < 3.0.7affected
Open-Xchange GmbHOX Dovecot Pro3.1.0 < 3.1.6affected
Open-Xchange GmbHOX Dovecot CE2.3.0 < 2.4.5affected

Weaknesses

  • CWE-416: Use After Free

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References