CVE-2026-29781 Sliver: Authenticated Nil-Pointer Dereference in Handlers
An authenticated attacker can crash the Sliver C2 server by sending malformed messages, causing a global denial of service for all active sessions.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-29781?
CVE-2026-29781 is a low-severity vulnerability in BishopFox sliver, published on 7 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
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.
Weakness: CWE-476
Which versions are affected by CVE-2026-29781?
3 open source packages ship an affected version, including github.com/bishopfox/sliver. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/bishopfox/sliver Go | All versions | None |
github.com/bishopfox/sliver Go | All versions to 1.7.3 | None |
github.com/bishopfox/sliver Go | All versions to 1.7.3 | None |
Products include Bishopfox Sliver.
How do I fix CVE-2026-29781?
No fix published yet.
Is CVE-2026-29781 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-29781 exists.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in BishopFox sliver
- CVE-2023-34758 Silver vulnerable to MitM attack against implants due to a cryptography vulnerability
- CVE-2026-25791 Sliver has a DNS C2 OTP Bypass Allows Unauthenticated Session Flooding and Denial of Service
- CVE-2025-27090 Server-Side Request Forgery (SSRF) in sliver teamserver
- CVE-2026-25760 Website Path Traversal / Arbitrary File Read (Authenticated) in Sliver
- CVE-2026-34227 Sliver One-Click Remote Access: Insecure CORS & Unauthenticated MCP Interface
Sources
Also known as GHSA-hx52-cv84-jr5v, GO-2026-4609.