CVE-2026-39830
CriticalCVSS 9.1Exploitation Probability (EPSS)
Low risk39th percentile — higher than 39% of all known CVEs
Summary
A malicious SSH peer can send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine cannot be released by calling Close(), causing a resource leak per connection. Unsolicited global responses are now discarded.
Risk Assessment
An attacker can exhaust SSH server resources by maintaining multiple connections with memory leaks, leading to denial of service (DoS).
Recommendation
Update the SSH library to a version that fixes this vulnerability by discarding unsolicited global responses and preventing resource leaks.
Original NVD description (English source)
A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close(), resulting in a resource leak per connection. Unsolicited global responses are now discarded.