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Vulnerability record · CVE-2026-25791 · published 9 February 2026

CVE-2026-25791: Bishopfox sliver missing authentication for critical function vulnerability

Bishopfox · Sliver

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.

7.5 CVSS 3.1 High EPSS 0.50% · top 60.0% CWE-306 · Missing authentication for critical functionCWE-400 · Uncontrolled resource consumption
7.5CVSS 3.1 base score
0.50%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References, 1 tagged exploit
17 Jun 2026Last modified by NVD

Description

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.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/BishopFox/sliver/releases/tag/v1.7.0 ProductRelease Notes
https://github.com/BishopFox/sliver/security/advisories/GHSA-wxrw-gvg8-fqjp ExploitVendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

8.1CVE-2023-34758Bishopfox sliver broken cryptographic algorithm vulnerabilitySliver from v1.5.x to v1.5.39 has an improper cryptographic implementation, which allows attackers to execute a man-in-the-middle attack via intercep…EPSS 0.59%6.9CVE-2025-27090Bishopfox sliver server-side request forgery (ssrf) vulnerabilitySliver is an open source cross-platform adversary emulation/red team framework, it can be used by organizations of all sizes to perform security test…EPSS 0.63%6.5CVE-2026-25760Bishopfox sliver path traversal vulnerabilitySliver is a command and control framework that uses a custom Wireguard netstack. Prior to 1.6.11, a path traversal in the website content subsystem l…EPSS 0.52%5.9CVE-2026-34227Bishopfox sliver missing authentication for critical function vulnerabilitySliver is a command and control framework that uses a custom Wireguard netstack. Prior to version 1.7.4, a single click on a malicious link gives an …EPSS 0.47%5.7CVE-2026-32941Bishopfox sliver allocation without limits vulnerabilitySliver is a command and control framework that uses a custom Wireguard netstack. Versions 1.7.3 and below contain a Remote OOM (Out-of-Memory) vulner…EPSS 0.44%2.1CVE-2026-29781Bishopfox sliver null pointer dereference vulnerabilitySliver is a command and control framework that uses a custom Wireguard netstack. In versions from 1.7.3 and prior, a vulnerability exists in the Sliv…EPSS 0.52%8.8CVE-2026-67277MikroTik RouterOS btest missing authentication leaks kernel memory and crashes kernelRouterOS accepts a "related" btest connection before the primary session is authenticated, letting an unauthenticated client start an IPv4 UDP test. …KEVEPSS 1.6%analysed8.8CVE-2026-59822LiteLLM MCP endpoint auth bypass via OAuth2 passthrough fallbackLiteLLM's MCP Streamable HTTP endpoint, prior to 1.84.0, let an unauthenticated attacker send a fabricated Authorization header that triggered an OAu…KEVEPSS 0.84%analysed

Source: NIST National Vulnerability Database (record CVE-2026-25791), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.