PT-2026-42713 · Go+1 · Golang.Org/X/Crypto+1

Published 2026-05-22 · Updated 2026-05-22 · CVE-2026-39834

Positive Technologies (AI Summary)

CVSS v3.1

9.1

Critical

Base vector

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

Name of the Vulnerable Software and Affected Versions The product name cannot be determined (affected versions not specified)

Description An integer overflow occurs during the internal payload size calculation when writing data exceeding 4GB in a single Write call on an SSH channel. This leads to a condition where the write loop spins indefinitely, resulting in the continuous transmission of empty packets without progressing the data transfer.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Related Identifiers

CVE-2026-39834

GO-2026-5020

Affected Products

Golang.Org/X/Crypto

Golang.Org/X/Crypto/Ssh

References · 6

• https://osv.dev/vulnerability/GO-2026-5020 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-39834 · Security Note
• https://groups.google.com/g/golang-announce/c/a082jnz-LvI · Note
• https://go.dev/cl/781663 · Note
• https://go.dev/issue/79567 · Note
• https://pkg.go.dev/vuln/GO-2026-5020 · Note