CVE-2026-42395 (GCVE-0-2026-42395)

Vulnerability from cvelistv5 – Published: 2026-08-28 10:12 – Updated: 2026-08-28 15:53
VLAI
Summary
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.
Severity
4.3 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 14:32 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version CPE status
Open-Xchange GmbH OX Dovecot Pro Affected: 2.3.0 , < 2.3.22.2 (semver)
Affected: 3.0.0 , < 3.0.7 (semver)
Affected: 3.1.0 , < 3.1.6 (semver)
guessed Create a notification for this product.
Open-Xchange GmbH OX Dovecot CE Affected: 2.3.0 , < 2.4.5 (semver)
guessed Create a notification for this product.
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.