CVE-2026-39834 (GCVE-0-2026-39834)

Vulnerability from cvelistv5 – Published: 2026-05-22 02:31 – Updated: 2026-05-22 18:50
VLAI
Title
Invoking infinite loop on large channel writes in golang.org/x/crypto/ssh
Summary
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.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-22 18:50 UTC
CWE
  • CWE-190 - Integer Overflow or Wraparound
Assigner
Go CNA under the Google root
CNA scorecard E 42/100 over 76 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
golang.org/x/crypto golang.org/x/crypto/ssh Affected: 0 , < 0.52.0 (semver)
guessed Create a notification for this product.
Credits
NCC Group Cryptography Services, sponsored by Teleport
Show details on NVD website
To clipboard 

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