CVE-2026-39834
CriticalCVSS 9.1Exploitation Probability (EPSS)
Low risk38th percentile - higher than 38% of all known CVEs
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 an infinite loop sending empty packets. The fix uses int64 for size comparison to prevent truncation.
Risk Assessment
An attacker could cause a denial of service by sending a large data packet, leading to an infinite loop and resource exhaustion on the SSH server.
Recommendation
Update the SSH library to a version that uses int64 for payload size calculation.
Original NVD description (English source)
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.