Open-Source Security Intelligence

Know every vulnerability
before it knows you.

DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.

Checkout DevGuardView on GitHub
Search

GHSA-vxx9-2994-q338

HighCVSS 8.7 / 10
Published Mar 13, 2026·Last modified Mar 16, 2026
Affected Components(0)

No affected components available

Description

Summary

The Rust implementation of Yamux can panic when processing a crafted inbound Data frame that sets SYN and uses a body length greater than DEFAULT_CREDIT (e.g. 262145). On the first packet of a new inbound stream, stream state is created and a receiver is queued before oversized-body validation completes. When validation fails, the temporary stream is dropped and cleanup may call remove(...).expect("stream not found"), triggering a panic in the connection state machine. This is remotely reachable over a normal Yamux session and does not require authentication. kind of vulnerability is it? Who is

Attack Scenario

An attacker that can establish a Yamux session with a target node can crash the target by sending a single validly encoded Yamux Data|SYN frame with an oversized body:

  1. Establish a standard authenticated transport session that negotiates Yamux.
  2. Send one Yamux frame with:
    • Tag = Data
    • Flags = SYN
    • StreamId = 1 (or any new inbound stream id)
    • Length = DEFAULT_CREDIT + 1 (e.g. 262145)
    • Body of matching size This can trigger a panic (stream not found) and terminate the process, depending on host application panic policy.

Patches

Users should upgrade to yamux v0.13.10

This vulnerability was originally submitted by @revofusion to the Ethereum Foundation bug bounty program

Risk Scores
Base Score
8.7

The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker does not need any special privileges or access rights. No user interaction is needed for the attacker to exploit this vulnerability.

Threat Intelligence
6.6

Exploitation attempts have been detected. Elevated vigilance and prompt remediation are advised.

EPSS
N/A

Probability that this vulnerability will be exploited in the wild within the next 30 days.

Exploit
Not available

We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.

Browse More

High severity
Scan your project

Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.

Checkout DevGuard