Unauthenticated CPU exhaustion via oversized SSH keys
Published May 22, 2026 · Updated Aug 28, 2026
Denial of service in golang.org/x/crypto/ssh before 0.52.0 allows remote attackers to exhaust CPU during public key authentication. The RSA and DSA public-key parsers accept unbounded key parameters and perform signature verification with attacker-sized integers. No account or user interaction is required; one crafted attempt can monopolize server CPU for several minutes and interrupt SSH service.
Summary
What happened
Denial of service in golang.org/x/crypto/ssh before 0.52.0 allows remote attackers to exhaust CPU during public key authentication. The RSA and DSA public-key parsers accept unbounded key parameters and perform signature verification with attacker-sized integers. No account or user interaction is required; one crafted attempt can monopolize server CPU for several minutes and interrupt SSH service.
The record
- CVE
- CVE-2026-39829
- Published
- May 22, 2026
- Updated
- Aug 28, 2026
- Vendor
- 389 Directory Server
- Product
- Assisted Installer for OpenShift Container Platform
- Classifications
- CWE-1284, 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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