Bishopfox: >> Sliver >> 1.4.10 Security Vulnerabilities
Sliver 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 unauthenticated attacker immediate, silent control over every active C2 session or beacon, capable of exfiltrating all collected target data (e.g. SSH keys, ntds.dit) or destroying the entire compromised infrastructure, entirely through the operator's own browser. This issue has been patched in version 1.7.4.
CVSS Score
8.8
EPSS Score
0.0
Published
2026-03-31
Sliver 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) vulnerability in the Sliver C2 server's mTLS and WireGuard C2 transport layer. The socketReadEnvelope and socketWGReadEnvelope functions trust an attacker-controlled 4-byte length prefix to allocate memory, with ServerMaxMessageSize allowing single allocations of up to ~2 GiB. A compromised implant or an attacker with valid credentials can exploit this by sending fabricated length prefixes over concurrent yamux streams (up to 128 per connection), forcing the server to attempt allocating ~256 GiB of memory and triggering an OS OOM kill. This crashes the Sliver server, disrupts all active implant sessions, and may degrade or kill other processes sharing the same host. The same pattern also affects all implant-side readers, which have no upper-bound check at all. The issue was not fixed at the the time of publication.
CVSS Score
6.5
EPSS Score
0.0
Published
2026-03-20
Sliver 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 Sliver C2 server's Protobuf unmarshalling logic due to a systemic lack of nil-pointer validation. By extracting valid implant credentials and omitting nested fields in a signed message, an authenticated actor can trigger an unhandled runtime panic. Because the mTLS, WireGuard, and DNS transport layers lack the panic recovery middleware present in the HTTP transport, this results in a global process termination. While requiring post-authentication access (a captured implant), this flaw effectively acts as an infrastructure "kill-switch," instantly severing all active sessions across the entire fleet and requiring a manual server restart to restore operations. At time of publication, there are no publicly available patches.
CVSS Score
6.5
EPSS Score
0.0
Published
2026-03-07
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 Score
7.5
EPSS Score
0.0
Published
2026-02-09
Sliver 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 lets an authenticated operator read arbitrary files on the Sliver server host. This is an authenticated path traversal / arbitrary file read issue, and it can expose credentials, configs, and keys. This vulnerability is fixed in 1.6.11.
CVSS Score
6.5
EPSS Score
0.0
Published
2026-02-06