Installing package triggers 3 high-severity advisories

[stxrtt]

Installing pi-backend results in three high-severity vulnerabilities reported by npm audit due to axios <=1.11.0 pulled in via stellar-sdk.

Reproduction
npm init -y
npm i pi-backend
npm audit --omit=dev

Observed (excerpt)

# npm audit report
axios  <=1.11.0
Severity: high
Axios Cross-Site Request Forgery Vulnerability - https://github.com/advisories/GHSA-wf5p-g6vw-rhxx
axios Requests Vulnerable To Possible SSRF and Credential Leakage via Absolute URL - https://github.com/advisories/GHSA-jr5f-v2jv-69x6      
Axios is vulnerable to DoS attack through lack of data size check - https://github.com/advisories/GHSA-4hjh-wcwx-xvwj
No fix available
node_modules/stellar-sdk/node_modules/axios
  stellar-sdk  <=10.4.1
  Depends on vulnerable versions of axios
  node_modules/stellar-sdk
    pi-backend  *
    Depends on vulnerable versions of stellar-sdk
    node_modules/pi-backend
3 high severity vulnerabilities

Impact
High-severity CSRF, SSRF, and DoS risks through axios used by stellar-sdk.

Proposed fix
Upgrade dependencies on both stellar-sdk and axios to the latest versions (14.2.0 and 1.12.2 respectively at the time of writing) and publish a patch release.