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

Summaryinfo

A vulnerability was found in Go x-crypto-ssh up to 0.55.x. It has been classified as problematic. This vulnerability affects unknown code. The manipulation leads to allocation of resources. This vulnerability is documented as CVE-2026-56855. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Go x-crypto-ssh up to 0.55.x and classified as problematic. This issue affects an unknown code block. The manipulation with an unknown input leads to a allocation of resources vulnerability. Using CWE to declare the problem leads to 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. Impacted is availability. The summary by CVE is:

Previously, after a channel has been established, a malicious peer could send crafted messages that would deadlock the entire connection. Now, we handle all RFC 4254 channel messages; global requests are handled explicitly. Then, treat all other messages as a protocol error and tear the connection down instead of buffering and blocking.

It is possible to read the advisory at go.dev. The identification of this vulnerability is CVE-2026-56855 since 06/23/2026. The exploitation is known to be easy. The attack may be initiated remotely. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading to version 0.56.0 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality 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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Entryinfo

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