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CVE-2026-25791 (GCVE-0-2026-25791)

Vulnerability from cvelistv5 – Published: 2026-02-09 20:34 – Updated: 2026-02-10 15:59
VLAI
Title
Sliver has a DNS C2 OTP Bypass Allows Unauthenticated Session Flooding and Denial of Service
Summary
Sliver is a command and control framework that uses a custom Wireguard netstack. Prior to 1.7.0, the DNS C2 listener accepts unauthenticated TOTP bootstrap messages and allocates server-side DNS sessions without validating OTP values, even when EnforceOTP is enabled. Because sessions are stored without a cleanup/expiry path in this flow, an unauthenticated remote actor can repeatedly create sessions and drive memory exhaustion. This vulnerability is fixed in 1.7.0.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-10 15:39 UTC
CWE
  • CWE-306 - Missing Authentication for Critical Function
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
References
Impacted products
Vendor Product Version CPE status
BishopFox sliver Affected: < 1.7.0
guessed Create a notification for this product.
Show details on NVD website
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