CVE-2026-32941 Sliver Vulnerable to Authenticated OOM via Memory Exhaustion in mTLS/WireGuard Transports
An authenticated attacker can crash the Sliver C2 server by sending crafted messages that trigger excessive memory allocation, disrupting 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-2026-32941?
CVE-2026-32941 is a medium-severity denial of service vulnerability in BishopFox sliver, published on 20 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. 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.
Which versions are affected by CVE-2026-32941?
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-2026-32941?
No fix published yet.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-32941 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-32941 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-97vp-pwqj-46qc, GO-2026-4723.