CVE-2026-420064.3MediumCWE-400

CVE-2026-42006: Open-Xchange GmbH OX Dovecot Pro vulnerability

Open-Xchange GmbH · OX Dovecot Pro

Vendor fix available · Affected: Open-Xchange GmbH OX Dovecot Pro · Exploitation: unlikely (under 1%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

0.6%probability of exploitation in the next 30 days

50th percentile

050100

Higher than 50% of scored CVEs

4.3MediumCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

An attacker can cause uncontrolled memory usage with excessive bracing over IMAP. The fix in CVE-2026-27857 was incomplete, only blocking one way of doing this, so there was still another way left open. In particular, the fix was for closing braces, but you could still use open braces to bypass the limit. Using excessive bracing, attacker can cause memory usage up to configured memory limit. Install fixed version, or configure vsz_limit for imap process to low value. No publicly available exploits are known.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

Open-Xchange GmbH · OX Dovecot Proup to and including 3.0.5; up to and including 3.1.4; up to and including 2.4.3

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Unlikely (under 1%). EPSS under 1%, or no score yet.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Uncontrolled Resource Consumption · Denial of Service
Vendor: Open-Xchange GmbH
Published: May 2026
Band: Unlikely (under 1%), May 2026

CoverageNo articles yet

No CyberSIXT article names CVE-2026-42006 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.

References

3 more references are in the CVE record.