CVE-2026-42395

MEDIUM
4.3
CVSS Score
Published: August 28, 2026 at 10:12 AM UTC
Updated: September 3, 2026 at 06:24 PM UTC
1 product affected across 1 vendorOX Dovecot

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Severity
MEDIUM4.3
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

Description

A host listed as a trusted proxy can send forwarding information containing a NUL byte, which crashes the login process on the following login attempt. The login process is terminated, which can cause degradation or denial of service for logins. 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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

2.3.0 ≤ v < 2.3.22.22.3.0 ≤ v < 2.4.53.0.0 ≤ v < 3.0.73.1.0 ≤ v < 3.1.62.3.03.0.03.1.0
Affected range stops below 2.3.22.2, so it looks safe — our inference, not a vendor statement
Affected range stops below 2.4.5, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.0.7, so it looks safe — our inference, not a vendor statement
Affected range stops below 3.1.6, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

4.3MEDIUMOX
Attack Vector
ADJACENT_NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-400

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