CVE-2026-18638Network attack vector

Authenticated server crash via missing-user password update

Published Aug 11, 2026 · Updated Aug 11, 2026

Denial of service in Rapid7 Velociraptor before 0.77.2 allows remote authenticated users to crash the server through SetPassword. The SetUserPassword path retains a failed GetUser result for a nonexistent username and continues with a nil user record instead of returning the error. Any account with at least the reader role in an organization can reach the API, and one crafted request terminates the entire server process.

CVSS severity6.5
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Rapid7 Velociraptor before 0.77.2 allows remote authenticated users to crash the server through SetPassword. The SetUserPassword path retains a failed GetUser result for a nonexistent username and continues with a nil user record instead of returning the error. Any account with at least the reader role in an organization can reach the API, and one crafted request terminates the entire server process.

The record

CVE
CVE-2026-18638
Published
Aug 11, 2026
Updated
Aug 11, 2026
Vendor
Rapid7
Product
Velociraptor
Classifications
CWE-703, CWE-476, CAPEC-153, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 11, 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.

  1. Affected versionversion=0 <0.77.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Rapid7 · Velociraptorversion=0 <0.77.2

Published CVSS scores

6.5Rapid7CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-703Improper Check or Handling of Exceptional Conditions
CWE-476NULL Pointer Dereference
CAPEC-153Input Data Manipulation
T1499.004Application or System Exploitation

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

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Your stack

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