GHSA-49pv-gwxp-532r
Fix: esm-dev/esm.sh@492de92GHSA-49pv-gwxp-532r is a CWE-23 vulnerability in github.com/esm-dev/esm.sh. O3 Security confirms whether GHSA-49pv-gwxp-532r is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
esm.sh has File Inclusion issue
Real-World Exposure
github.com/esm-dev/esm.shReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A Local File Inclusion (LFI) issue was identified in the esm.sh service URL handling. An attacker could craft a request that causes the server to read and return files from the host filesystem (or other unintended file sources).
Severity: High — LFI can expose secrets, configuration files, credentials, or enable further compromise. Impact: reading configuration files, private keys, environment files, or other sensitive files; disclosure of secrets or credentials; information leakage that could enable further attacks.
Vulnerable code snippet is in this file: https://github.com/esm-dev/esm.sh/blob/c62f191d32639314ff0525d1c3c0e19ea2b16143/server/router.go#L1168
Proof of Concept
- Using this default config file that I copy from the repo, the server is running at
http://localhost:9999with this commandgo run server/esmd/main.go --config=config.json
{
"port": 9999,
"npmRegistry": "https://registry.npmjs.org/",
"npmToken": "******"
}
- Trigger the LFI vulnerability by sending this command below to read a local file
# read /etc/passwd
curl --path-as-is 'http://localhost:9999/pr/x/y@99/../../../../../../../../../../etc/passwd?raw=1&module=1'
# or read the database esm.db file
curl --path-as-is 'http://localhost:9999/pr/x/y@99/../../../../../../../esm.db?raw=1&module=1'
Remediation
Simply remove any .. in the URL path before actually process the file. See more details in this guide
Credits
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/esm-dev/esm.sh | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/esm-dev/esm.sh. 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.
Remediation status
No patched version of github.com/esm-dev/esm.sh has shipped for GHSA-49pv-gwxp-532r yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
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-49pv-gwxp-532r 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-49pv-gwxp-532r. 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-49pv-gwxp-532r in your dependencies?
O3 detects GHSA-49pv-gwxp-532r across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.