GHSA-qwrf-gfpj-qvj6
Smokescreen SSRF via deny list bypass (square brackets)
Packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| Go | github.com/stripe/smokescreen | < 0.0.4 | 0.0.4 |
Details
As written in the advisory (Markdown source, shown as plain text).
### Impact
The primary use case for Smokescreen is to prevent server-side request forgery (SSRF) attacks in which external attackers leverage the behavior of applications to connect to or scan internal infrastructure.
Smokescreen also offers an option to deny access to additional (e.g., external) URLs by way of a deny list. There was an issue in Smokescreen that made it possible to bypass the deny list feature by surrounding the hostname with square brackets (e.g. `[example.com]`).
### Recommendation
Upgrade Smokescreen to version 0.0.4 or later.
### Acknowledgements
Thanks to [Axel Chong](https://github.com/haxatron) for reporting the issue.
### For more information
Email us at [email protected]
References
External links from the advisory. They lead to third-party sites.