CVE-2026-25791 (GCVE-0-2026-25791)
Vulnerability from cvelistv5 – Published: 2026-02-09 20:34 – Updated: 2026-02-10 15:59
VLAI
EPSS
VEX
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)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-10 15:39 UTC
CWE
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/BishopFox/sliver/security/advi… | x_refsource_CONFIRM |
| https://github.com/BishopFox/sliver/releases/tag/v1.7.0 | x_refsource_MISC |
Impacted products
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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