Resource Leak in golang.org/x/crypto/ssh <0.52.0 via Global Request Buffers
CVE-2026-39830 Published on May 22, 2026
Invoking client can cause server deadlock on unexpected responses in golang.org/x/crypto/ssh
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.
Vulnerability Analysis
CVE-2026-39830 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality, with no impact on integrity, and a high impact on availability.
Products Associated with CVE-2026-39830
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Affected Versions
golang.org/x/crypto/ssh:- Before 0.52.0 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.