CVE-2025-6444
mediumpriority · track · 24EPSS 0.005 · 42 %ileEUUSEPSS · scored 2026-10-28
ServiceStack GetErrorResponse Improper Input Validation NTLM Relay Vulnerability. This vulnerability allows remote attackers to relay NTLM credentials on affected installations of ServiceStack. Interaction with this library is required to exploit this vulnerability but attack vectors may vary depending on the implementation. The specific flaw exists within the implementation of the GetErrorResponse method. The issue results from the lack of proper validation of user-supplied data, which can result in a type confusion condition. An attacker can leverage this vulnerability to relay NTLM credentials in the context of the current user. Was ZDI-CAN-25834.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (5)
External citations — patches, advisories, analysis.
- https://docs.servicestack.net/releases/v8_06#zdi-can-25837Patchcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2025-6444cnnvd
- https://www.zerodayinitiative.com/advisories/ZDI-25-415/cnnvd
- https://www.zerodayinitiative.com/advisories/ZDI-25-415/enisa_euvd
- https://www.zerodayinitiative.com/advisories/ZDI-25-415/Third Party Advisorynvd
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