CVE-2026-39834

Published: May 22, 2026Modified: Jul 23, 2026

9.1

Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Exploitability: 3.9 / Impact: 5.2

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)

Description

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.

Affected (1)

Products: Golang: Crypto

1 product

Configuration A

1 vulnerable

Vulnerable Software	Affected Versions
Golang Crypto	Before 0.52.0

Related CWEs

Integer Overflow or Wraparound

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 occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

References (4)

https://go.dev/cl/781663

Source: security@golang.org

Issue Tracking

https://go.dev/issue/79567

Source: security@golang.org

Issue Tracking

https://groups.google.com/g/golang-announce/c/a082jnz-LvI

Source: security@golang.org

Mailing List

https://pkg.go.dev/vuln/GO-2026-5020

Source: security@golang.org

Vendor Advisory

Timeline

No history available yet.