CVE-2026-18638: CWE-476 NULL pointer dereference in Rapid7 Velociraptor
CVE-2026-18638 is a medium severity vulnerability in Rapid7 Velociraptor versions prior to 0.77.2. It allows any authenticated user, including those with only reader role privileges, to cause a denial of service by terminating the entire server process. This is triggered by sending a SetPassword request with a username that does not exist, resulting in a NULL pointer dereference.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-18638) in Rapid7 Velociraptor involves a NULL pointer dereference (CWE-476) that can be exploited by any authenticated user, including those with minimal privileges (reader role). By invoking the SetPassword function with a non-existent username, the server process crashes, causing a denial of service. The vulnerability affects versions prior to 0.77.2. No official remediation or patch information is currently available.
Potential Impact
The impact is a denial of service (DoS) condition where the entire Velociraptor server process is terminated. This can disrupt monitoring and incident response activities relying on the Velociraptor server. There is no impact on confidentiality or integrity according to the CVSS vector.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict authenticated user access to trusted personnel only and monitor for unusual SetPassword requests with invalid usernames to reduce risk.
CVE-2026-18638: CWE-476 NULL pointer dereference in Rapid7 Velociraptor
Description
CVE-2026-18638 is a medium severity vulnerability in Rapid7 Velociraptor versions prior to 0.77.2. It allows any authenticated user, including those with only reader role privileges, to cause a denial of service by terminating the entire server process. This is triggered by sending a SetPassword request with a username that does not exist, resulting in a NULL pointer dereference.
CVSS v3.1
Score 6.5medium
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-18638) in Rapid7 Velociraptor involves a NULL pointer dereference (CWE-476) that can be exploited by any authenticated user, including those with minimal privileges (reader role). By invoking the SetPassword function with a non-existent username, the server process crashes, causing a denial of service. The vulnerability affects versions prior to 0.77.2. No official remediation or patch information is currently available.
Potential Impact
The impact is a denial of service (DoS) condition where the entire Velociraptor server process is terminated. This can disrupt monitoring and incident response activities relying on the Velociraptor server. There is no impact on confidentiality or integrity according to the CVSS vector.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict authenticated user access to trusted personnel only and monitor for unusual SetPassword requests with invalid usernames to reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- rapid7
- Date Reserved
- 2026-08-03T10:45:04.075Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a7b3f3abf8831d539f2adf6
Added to database: 08/11/2026, 15:26:50 UTC
Last enriched: 08/11/2026, 15:47:34 UTC
Last updated: 08/11/2026, 16:00:07 UTC
Views: 4
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