Authenticated KDC crash via six-byte buffer over-read
Published Jul 30, 2026 · Updated Jul 30, 2026
Out-of-bounds read in Samba 4.0 and later allows remote authenticated users to crash a KDC process via malformed kpasswd requests. The kpasswd parser miscalculates an ASN.1 structure's size by six bytes and reads beyond the allocated buffer. Only Samba Active Directory domain controllers with kpasswd enabled are exposed, and exploitation is unreliable but can terminate the KDC after many attempts.
Summary
What happened
Out-of-bounds read in Samba 4.0 and later allows remote authenticated users to crash a KDC process via malformed kpasswd requests. The kpasswd parser miscalculates an ASN.1 structure's size by six bytes and reads beyond the allocated buffer. Only Samba Active Directory domain controllers with kpasswd enabled are exposed, and exploitation is unreliable but can terminate the KDC after many attempts.
The record
- CVE
- CVE-2026-58216
- Published
- Jul 30, 2026
- Updated
- Jul 30, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-125, T1499.004
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 30, 2026CVE publishedPublication date reported by the CVE source.
- Jul 30, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo