Account impersonation via reusable password-hash login
Published Nov 28, 2022 · Updated Apr 25, 2025
Improper authentication in Velneo vClient 28.1.3 allows remote attackers with a username and password hash to impersonate that user. The client login sends the reusable password hash to vServer, which accepts it as authentication proof instead of requiring knowledge of the password. Possession of both values is required and grants the victim's application access and identity without an existing authenticated session.
Summary
What happened
Improper authentication in Velneo vClient 28.1.3 allows remote attackers with a username and password hash to impersonate that user. The client login sends the reusable password hash to vServer, which accepts it as authentication proof instead of requiring knowledge of the password. Possession of both values is required and grants the victim's application access and identity without an existing authenticated session.
The record
- CVE
- CVE-2021-45036
- Published
- Nov 28, 2022
- Updated
- Apr 25, 2025
- Vendor
- Velneo
- Product
- Velneo vClient
- Classifications
- CWE-290, T1550.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Nov 28, 2022CVE publishedPublication date reported by the CVE source.
- Apr 25, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=28.1.3
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.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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