AIKIDO-2026-335387
russh is vulnerable to Denial of Service (DoS)
37
Low Risk
This Affects:
russhTL;DR
russh allows a block cipher that requires message authentication, such as AES-CBC, AES-CTR, or 3DES-CBC, to be negotiated together with mac=none, because the MAC-selection logic only checks cipher and MAC pairing when negotiation would otherwise fail. With no MAC in place, a peer can send a packet whose decrypted length field is zero, shrinking the input buffer below already-buffered data and triggering a slice index panic. This crashes the affected SSH connection. The fix rejects or substitutes mac=none whenever the chosen cipher needs a MAC and guards against buffer shrinkage below consumed bytes.
Who does this affect?
You are affected if you are using a version that falls within the vulnerable range and a connection negotiates a MAC-requiring block cipher (such as AES-CBC, AES-CTR, or 3DES-CBC) together with mac=none, which lets an untrusted peer send a crafted packet that panics the connection task.
Background info
russh is vulnerable to Denial of Service (DoS) in versions 0.0.1 - 0.63.0.
How to fix this
Upgrade the russh library to the patch version.
Are You Affected?
Connect your repositories to instantly see whether vulnerable or malicious packages exist in your codebase.
Free. No credit card required.
I consent to receiving marketing communications based on Aikido’s Privacy Policy.
SOC 2Compliant
ISO 27001CompliantISO 42001Compliant
FedRAMPImplementing© All Intel data is openly available and commercially licensed.