CVE-2026-32941
MEDIUMSliver Vulnerable to Authenticated OOM via Memory Exhaustion in mTLS/WireGuard Transports
Title source: cnaExploitation Summary
EIP tracks 2 public exploits for CVE-2026-32941. PoCs published by XZ1r0, skoveit.
AI-analyzed exploit summary This repository contains a functional Go-based PoC for CVE-2026-32941, demonstrating an OOM DoS attack against Sliver C2 servers by abusing uncontrolled memory allocation in the socketReadEnvelope function via crafted length prefixes.
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.
Exploits (2)
This repository contains a functional Go-based PoC for CVE-2026-32941, demonstrating an OOM DoS attack against Sliver C2 servers by abusing uncontrolled memory allocation in the socketReadEnvelope function via crafted length prefixes.
This repository contains a functional exploit PoC for CVE-2026-32941, a Denial of Service (DoS) vulnerability in Sliver C2. The exploit abuses uncontrolled memory allocation in the socketReadEnvelope function by sending a malicious uint32 length prefix, leading to an OOM crash of the Sliver server.
References (1)
Scores
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H