Putting it together
The regex isn't perfect yet (it can match partial matches and so on)

Usage example (in the source code directory):
./cve.py CVE-2024-45338

#!/usr/bin/env python3

import requests
import json
from lxml import html
import sys
import subprocess


results = []
def find_pkg_go(obj):
    if isinstance(obj, dict):
        for k, v in obj.items():
            find_pkg_go(v)
    elif isinstance(obj, list):
        for item in obj:
            find_pkg_go(item)
    elif isinstance(obj, str) and "pkg.go" in obj:
        results.append(obj)


if len(sys.argv) != 2:
    print("Usage: cve.py <CVE-ID>")
    exit(1)

cve_id = sys.argv[1]

url = f"https://api.osv.dev/v1/vulns/{cve_id}"

response = requests.get(url)
data = response.json()
find_pkg_go(data)

if len(results) != 1:
    print("can't find go package URL")
    exit(1)

url = results[0]
response = requests.get(url)
tree = html.fromstring(response.content)

symbols_div = tree.xpath('//div[@class="VulnEntryPackages-attr VulnEntryPackages-symbols"]')[0]
symbols = symbols_div.xpath('.//ul/li/a/text()')

package_name = symbols_div.xpath('.//ul/li/a/@href')[0].split('#')[0].lstrip('/')

for symbol in symbols:
    cmd = f'callgraph -format=digraph ./... | digraph nodes | grep -E "{package_name}.*{symbol}"'
    print(cmd)
    result = subprocess.run(cmd, shell=True)
    if result.returncode == 0:
        sys.exit(1)

print("No symbols found")