Remote SSH service exhaustion via unsolicited responses
Published May 22, 2026 · Updated Aug 28, 2026
Resource exhaustion in golang.org/x/crypto/ssh before 0.52.0 allows remote attackers to interrupt SSH services via unsolicited responses. The SSH connection read loop queues unsolicited global-request replies into a bounded internal channel until the receiving goroutine blocks, and Close cannot release it. An unauthenticated malicious SSH peer can repeat the condition across connections, leaking one blocked goroutine and associated resources per connection.
Summary
What happened
Resource exhaustion in golang.org/x/crypto/ssh before 0.52.0 allows remote attackers to interrupt SSH services via unsolicited responses. The SSH connection read loop queues unsolicited global-request replies into a bounded internal channel until the receiving goroutine blocks, and Close cannot release it. An unauthenticated malicious SSH peer can repeat the condition across connections, leaking one blocked goroutine and associated resources per connection.
The record
- CVE
- CVE-2026-39830
- Published
- May 22, 2026
- Updated
- Aug 28, 2026
- Vendor
- 389 Directory Server
- Product
- Assisted Installer for OpenShift Container Platform
- Classifications
- CWE-119, CWE-772, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 22, 2026CVE publishedPublication date reported by the CVE source.
- Aug 28, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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