Go x-crypto-ssh up to 0.55.x Channel handlePacket allocation of resources

Summaryinfo

A vulnerability was found in Go x-crypto-ssh up to 0.55.x. It has been declared as problematic. This issue affects the function handlePacket of the component Channel. The manipulation results in allocation of resources. This vulnerability is reported as CVE-2026-78662. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Go x-crypto-ssh up to 0.55.x. It has been classified as problematic. Affected is the function handlePacket of the component Channel. The manipulation with an unknown input leads to a allocation of resources vulnerability. CWE is classifying the issue as CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. This is going to have an impact on availability. CVE summarizes:

Previously, a channel registered in the mux's chanList is not usable until it is established. A malicious peer was able flood the channel's incomingRequests, deadlocking the entire connection. Now, we add an atomic established state, set when a channel becomes usable. Until such a time, handlePacket drops every packet other than the open confirmation/failure, without blocking and without tearing down the connection.

The advisory is shared for download at go.dev. This vulnerability is traded as CVE-2026-78662 since 08/25/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 0.56.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• SSH Server Software

Vendor

• Go

Name

• x-crypto-ssh

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15
• 0.16
• 0.17
• 0.18
• 0.19
• 0.20
• 0.21
• 0.22
• 0.23
• 0.24
• 0.25
• 0.26
• 0.27
• 0.28
• 0.29
• 0.30
• 0.31
• 0.32
• 0.33
• 0.34
• 0.35
• 0.36
• 0.37
• 0.38
• 0.39
• 0.40
• 0.41
• 0.42
• 0.43
• 0.44
• 0.45
• 0.46
• 0.47
• 0.48
• 0.49
• 0.50
• 0.51
• 0.52
• 0.53
• 0.54
• 0.55

CPE 2.3info

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CPE 2.2info

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