CVE-2026-32314CWE-248

Yamux remote Panic via malformed Data frame with SYN set and len = 262145

High · published March 13, 2026

CVSS v4.0
8.7
EPSS
1%
Percentile
47.8
In the wild
Unconfirmed
What it is

Yamux is a stream multiplexer over reliable, ordered connections such as TCP/IP. Prior to 0.13.10, 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. This vulnerability is fixed in 0.13.10.

The record
Technical detail
CVSS v4.0
8.7 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
EPSS
0.00595 · 47.8th percentile
Weakness
CWE-248 · Uncaught Exception
Published
2026-03-13T19:53Z
EPSS history
Timeline
  • 13 MAR 19:53Z
    Yamux remote Panic via malformed Data frame with SYN set and len = 262145
    cvelistv5