Hello @aleynasahin
I've made extensive investigation regarding this.
TLDR: it's not possible to use the action "Invoke Web Service" to send file attachments to JIRA. Use "DOS command" action and cURL instead.
Regarding sending attachments to JIRA using the action "Invoke Web Service". You can solve the issue "XSRF Check Failed" by adding following headers:
X-Atlassian-Token: nocheck
Authorization: Basic <base64>
User-Agent: PowerAutomateDesktop/1.0.0
Base64 is the username (email) + ":" + API key (generated in JIRA). But the real problem is, it's not possible to send binary data with this action. JIRA only supports binary files, it does not accept base64 encoding: https://jira.atlassian.com/browse/JRACLOUD-60930
Therefore, use the DOS command action and cURL instead. cURL will automatically base64 encode your credentials and send the binary file.
Here is the complete solution: https://power.automate.gallery/send-file-attachments-to-jira-issues-using-curl