GHSA-wm7q-rxch-43mx
Byass due to validation before canonicalization in serve
Versions of serve before 6.5.2 are vulnerable to the bypass of the ignore functionality. The bypass is possible because validation happens before canonicalization of paths and filenames.
Example: Here we have a server that ignores the file test.txt.
const serve = require('serve')
const server = serve(__dirname, {
port: 1337,
ignore: ['test.txt']
})
Using the URL encoded form of a letter (%65 instead of e) attacker can bypass the ignore control accessing the file.
curl http://localhost:1337/t%65st.txt
Additionally this technique can be used to get directory listings of ignored directories.
Recommendation
Update to version 6.5.2 or later.
What each source reports
GitHub AdvisoriesNo score
Byass due to validation before canonicalization in serve
Versions of serve before 6.5.2 are vulnerable to the bypass of the ignore functionality. The bypass is possible because validation happens before canonicalization of paths and filenames.
Example: Here we have a server that ignores the file test.txt.
const serve = require('serve')
const server = serve(__dirname, {
port: 1337,
ignore: ['test.txt']
})
Using the URL encoded form of a letter (%65 instead of e) attacker can bypass the ignore control accessing the file.
curl http://localhost:1337/t%65st.txt
Additionally this technique can be used to get directory listings of ignored directories.
Recommendation
Update to version 6.5.2 or later.
- Record
GHSA-wm7q-rxch-43mx- Updated
- 2026-11-02
OSVNo score
Byass due to validation before canonicalization in serve
Versions of serve before 6.5.2 are vulnerable to the bypass of the ignore functionality. The bypass is possible because validation happens before canonicalization of paths and filenames.
Example: Here we have a server that ignores the file test.txt.
const serve = require('serve')
const server = serve(__dirname, {
port: 1337,
ignore: ['test.txt']
})
Using the URL encoded form of a letter (%65 instead of e) attacker can bypass the ignore control accessing the file.
curl http://localhost:1337/t%65st.txt
Additionally this technique can be used to get directory listings of ignored directories.
Recommendation
Update to version 6.5.2 or later.
- Record
GHSA-wm7q-rxch-43mx- Updated
- 2026-11-02
Affected packages
| Package | Affected | Fixed |
|---|---|---|
servenpm | before 6.5.2 | 6.5.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | GitHub Advisories, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
GHSA-wm7q-rxch-43mx is a vulnerability with no CVSS score yet in serve, published September 1, 2020. No source lists public exploit code. Fixed in serve 6.5.2.