Unauthenticated service interruption via concurrent HTTP floods
Published Jan 15, 2026 · Updated Jan 15, 2026
Denial of service in Sylkat-Tools AWebServer GhostBuilding 18 allows remote attackers to crash or hang its HTTP service via request floods. The public exploit starts attacker-selected numbers of threads that loop indefinitely, issuing GET requests to the server root and /mysqladmin without encountering effective request throttling. No authentication or user interaction is required; the demonstrated consequence is loss of service availability, not data access or modification.
Summary
What happened
Denial of service in Sylkat-Tools AWebServer GhostBuilding 18 allows remote attackers to crash or hang its HTTP service via request floods. The public exploit starts attacker-selected numbers of threads that loop indefinitely, issuing GET requests to the server root and /mysqladmin without encountering effective request throttling. No authentication or user interaction is required; the demonstrated consequence is loss of service availability, not data access or modification.
The record
- CVE
- CVE-2021-47752
- Published
- Jan 15, 2026
- Updated
- Jan 15, 2026
- Vendor
- Sylkat-Tools
- Product
- AWebServer
- Classifications
- CWE-770, T1499.003
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 15, 2026CVE publishedPublication date reported by the CVE source.
- Jan 15, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=AWebServer GhostBuilding 18
What conditions does exploitation require?
What is affected?
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.
Weakness, pattern, technique
Public exploit references
- AWebServer GhostBuilding 18 denial-of-service scriptfunctional · demonstrated
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Technologies
Your stack
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Your stack
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