CVE-2026-42008
Last modified
CVE-2026-42008 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. Forwarding information received from a host listed as a trusted proxy is not kept separate from Dovecot's own authentication fields, so a value sent by that host can be injected as an internal authentication field. Any host permitted to act as a trusted proxy can authenticate as any user without knowing that user's password. EPSS estimates a 0.19% chance of exploitation in the next 30 days.
Description
Forwarding information received from a host listed as a trusted proxy is not kept separate from Dovecot's own authentication fields, so a value sent by that host can be injected as an internal authentication field. Any host permitted to act as a trusted proxy can authenticate as any user without knowing that user's password. This affects deployments whose password database honours a field that permits authentication without a password. Deployments that do not configure trusted proxies are not affected. Restrict the list of trusted proxy networks to hosts that are fully under your control. Update to non-vulnerable version. No publicly available exploits are known.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Open-Xchange GmbH | OX Dovecot Pro | >= 2.3.4, < 2.3.22.2; >= 3.0.0, < 3.0.7; >= 3.1.0, < 3.1.6 |
| Open-Xchange GmbH | OX Dovecot CE | >= 2.3.4, < 2.4.5 |
References
Timeline
- Published
- Last Modified
- Status
- Deferred
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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