ModSecurity 2.9.7 install on Windows is blocking access to some local URL

Describe the bug

Hi, we found that installing ModSec 2.9.7 on an application server, it is breaking our Test Execution Framework tests. A prent site is accessible no problem

https://ab1.testsite.com works fine

BUT

If i run a curl to

https://ab1.testsite.com/mw/ws/lui/luinternal.asmx

It times out

Works fine on an identical server with no Modsec installed

Logs and dumps

Output of:

1. DebugLogs (level 9) - Nothing shows in the debug log for this behaviour even when set to the highest level
2. AuditLogs - Nothing shows in the audit log for this behaviour even when set to the highest level
3. Error logs - Nothing in the error logs
4. If there is a crash, the core dump file. - No dump file

Notice: Be carefully to not leak any confidential information.

To Reproduce

Steps to reproduce the behavior:

See above for steps to reproduce

Expected behavior

A clear and concise description of what you expected to happen.

Should see curl complete full access to the site

Instead it just hangs

• Trying x.x.x.x:443...
• TCP_NODELAY set
• Connected to x.x.x.x (x.x.x.x) port 443 (#0)
• ALPN, offering h2
• ALPN, offering http/1.1
• TLSv1.3 (OUT), TLS handshake, Client hello (1):
• TLSv1.3 (IN), TLS handshake, Server hello (2):
• TLSv1.2 (IN), TLS handshake, Certificate (11):
• TLSv1.2 (IN), TLS handshake, Server key exchange (12):
• TLSv1.2 (IN), TLS handshake, Server finished (14):
• TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
• TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):
• TLSv1.2 (OUT), TLS handshake, Finished (20):
• TLSv1.2 (IN), TLS handshake, Finished (20):
• SSL connection using TLSv1.2 / ECDHE-RSA-AES256-GCM-SHA384
• ALPN, server did not agree to a protocol
• Server certificate:
• subject: CN=*.testsite.com
• start date: Jan 2 17:07:23 2025 GMT
• expire date: Mar 9 23:04:06 2026 GMT
• issuer: DC=com; DC=testsite; CN=testsite.com
• SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.

GET /mw/ws/lui/lu/internal.asmx HTTP/1.1
Host: ab1.testsite.com
User-Agent: curl/7.67.0
Accept: /

^C

Rule Set (please complete the following information):

No rule is being used

Additional context

None

No source file, test, rule, or diagnostic entry point is identified. Start by reproducing the ModSecurity 2.9.7 Windows setup with curl against the stated URL, then compare it with the identical server without ModSecurity and inspect the debug, audit, and error logs; done means identifying the cause of the hang and documenting a verified fix or configuration change.