CVE-2025-70042: ThermaKube SSRF Vulnerability

CVE-2025-70042 Overview

A Server-Side Request Forgery (SSRF) vulnerability has been discovered in oslabs-beta ThermaKube master. This vulnerability, classified under CWE-918, allows an attacker to induce the server-side application to make HTTP requests to an arbitrary domain of the attacker's choosing. SSRF flaws occur when a web application fetches a remote resource without validating the user-supplied URL, enabling attackers to coerce the application to send crafted requests to unexpected destinations.

Critical Impact

This SSRF vulnerability in ThermaKube allows unauthenticated remote attackers to perform server-side requests that could lead to internal network reconnaissance, access to cloud metadata services, and potential full system compromise through chained attacks.

Affected Products

• oslabs-beta ThermaKube master branch

Discovery Timeline

• 2026-03-09 - CVE CVE-2025-70042 published to NVD
• 2026-03-11 - Last updated in NVD database

Technical Details for CVE-2025-70042

Vulnerability Analysis

This vulnerability represents a Server-Side Request Forgery (SSRF) flaw in the ThermaKube application, an open-source project maintained under the oslabs-beta organization. SSRF vulnerabilities are particularly dangerous in containerized and Kubernetes environments like ThermaKube operates in, as they can be leveraged to access internal services, cloud provider metadata endpoints, and other sensitive resources not intended to be publicly accessible.

The vulnerability exists in the master branch of the ThermaKube project. An attacker exploiting this flaw could manipulate server-side requests to access internal network resources, potentially exposing sensitive configuration data, service account credentials, or enabling lateral movement within a Kubernetes cluster.

Root Cause

The root cause of this vulnerability stems from insufficient validation of user-supplied URLs or request parameters before the application processes server-side HTTP requests. When ThermaKube accepts input that influences the destination of outbound requests without proper sanitization, attackers can redirect these requests to internal or external targets of their choosing. This typically occurs when URL parameters, headers, or other user-controllable inputs are directly incorporated into backend HTTP requests without allowlist validation or URL parsing checks.

Attack Vector

The vulnerability is exploitable over the network without requiring authentication or user interaction. An attacker can craft malicious requests that cause the ThermaKube server to:

1. Access internal services by specifying internal IP addresses or hostnames
2. Retrieve cloud provider metadata (e.g., http://169.254.169.254/ on AWS, GCP, or Azure)
3. Scan internal network ports to enumerate available services
4. Potentially bypass firewall restrictions by leveraging the server as a proxy

The attack can be executed remotely against any exposed ThermaKube instance running the vulnerable master branch code. A proof-of-concept demonstrating the exploitation technique is available through the GitHub Gist PoC.

Detection Methods for CVE-2025-70042

Indicators of Compromise

• Unusual outbound HTTP/HTTPS requests from the ThermaKube application to internal IP ranges (e.g., 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16)
• HTTP requests to cloud metadata endpoints such as 169.254.169.254 originating from application servers
• Unexpected DNS resolution requests for internal hostnames from the ThermaKube service
• Server logs showing requests with manipulated URL parameters pointing to internal or unexpected external destinations

Detection Strategies

• Monitor network traffic for SSRF patterns including requests to localhost, private IP ranges, and cloud metadata services
• Implement egress filtering and log all outbound connections from ThermaKube containers
• Deploy web application firewall (WAF) rules to detect and block common SSRF payloads in request parameters
• Use SentinelOne Singularity XDR to correlate network anomalies with application behavior for real-time SSRF detection

Monitoring Recommendations

• Enable verbose logging for all HTTP client libraries used by ThermaKube
• Set up alerts for any requests to the cloud metadata service IP range (169.254.0.0/16)
• Monitor for DNS queries to internal service names from unexpected sources
• Implement network segmentation monitoring to detect cross-boundary access attempts

How to Mitigate CVE-2025-70042

Immediate Actions Required

• Audit any ThermaKube deployments running the master branch for exposure to untrusted networks
• Implement network-level egress filtering to restrict outbound connections from ThermaKube to known-good destinations only
• Deploy a web application firewall (WAF) with SSRF detection rules in front of ThermaKube instances
• Review application logs for evidence of prior exploitation attempts

Patch Information

As of the last modification date (2026-03-11), no official patch has been released by the oslabs-beta maintainers. Users should monitor the ThermaKube Project Repository for security updates and patch releases. The vulnerability affects the master branch, so any commits addressing SSRF validation should be reviewed and applied when available.

Workarounds

• Implement strict URL allowlisting at the application level to restrict destinations for server-side requests
• Block access to internal IP ranges and cloud metadata endpoints at the network/firewall level for ThermaKube pods
• Use a forward proxy with destination restrictions for all outbound HTTP requests from the application
• Disable or remove the vulnerable functionality if it is not critical to operations until a patch is available
• Consider running ThermaKube in an isolated network segment with no access to sensitive internal resources

# Example: Block cloud metadata and internal ranges using iptables on the ThermaKube host
# Block AWS/GCP/Azure metadata service
iptables -A OUTPUT -d 169.254.169.254 -j DROP

# Block common internal IP ranges
iptables -A OUTPUT -d 10.0.0.0/8 -j DROP
iptables -A OUTPUT -d 172.16.0.0/12 -j DROP
iptables -A OUTPUT -d 192.168.0.0/16 -j DROP

# For Kubernetes, consider using NetworkPolicies to restrict egress
# Apply this NetworkPolicy to the ThermaKube namespace