CVE-2025-6444 ServiceStack GetErrorResponse Improper Input Validation NTLM Relay Vulnerability
Remote attackers can relay NTLM credentials via improper input validation in ServiceStack's GetErrorResponse method, potentially leading to account takeover.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-6444?
CVE-2025-6444 is a medium-severity vulnerability in ServiceStack, published on 25 Jun 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-20
Which versions are affected by CVE-2025-6444?
It affects 1 product.
Products include Servicestack Servicestack.
How do I fix CVE-2025-6444?
No fix has been published for CVE-2025-6444 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-6444 being exploited?
There is no known exploitation of CVE-2025-6444 in the wild and no public exploit code.
Other vulnerabilities in ServiceStack
Sources
Also known as GHSA-2cp7-3mjq-769q.