There is a tool called jira-tickets-for-new-vulns, it provides the means to sync your Snyk-monitored projects and automatically open Jira tickets for new issues and existing issue(s) without ticket(s) already created.
Cron it every X minutes/hours and fix the issues. This tool is aimed to be executed at regular intervals or with a trigger of your choice (webhooks). It can be could like this:
./snyk-jira-sync-<yourplatform>
-orgID=<SNYK_ORG_ID> // Can find it under settings
-token=<API Token> // Snyk API Token. Service accounts work.
-jiraProjectKey=<Key> // Jira project Key the tickets will be opened against
--severity=critical // optional: critical|high|medium|low
You can also find some extended options to set this up, for example apply this just for 'High' severity vulnerabilities and above.