x-crypto up to 0.51.x integer overflow

Summaryinfo

A vulnerability marked as problematic has been reported in x-crypto up to 0.51.x. This affects an unknown function. This manipulation causes integer overflow. This vulnerability is handled as CVE-2026-39834. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in x-crypto up to 0.51.x. Affected by this vulnerability is an unknown code. The manipulation with an unknown input leads to a integer overflow vulnerability. The CWE definition for the vulnerability is CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. As an impact it is known to affect availability. The summary by CVE is:

When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

It is possible to read the advisory at go.dev. This vulnerability is known as CVE-2026-39834 since 04/07/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 316559 (Linux Distros Unpatched Vulnerability : CVE-2026-39834), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 0.52.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (316559), EUVD (EUVD-2026-31400) and CERT Bund (WID-SEC-2026-1653). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Amazon Linux 2
• Red Hat Enterprise Linux
• Fedora Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• RESF Rocky Linux
• IBM MQ
• Golang Go
• SUSE openSUSE
• Red Hat OpenShift

Productinfo

Name

• x-crypto

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

CPE 2.3info

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CPE 2.2info

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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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