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Smokescreen SSRF via deny list bypass (square brackets)

Moderate
jjiang-stripe published GHSA-qwrf-gfpj-qvj6 May 10, 2022

Package

gomod smokescreen (Go)

Affected versions

< 0.0.4

Patched versions

0.0.4

Description

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 for reporting the issue.

For more information

Email us at security@stripe.com

Severity

Moderate
5.3
/ 10

CVSS base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CVE ID

CVE-2022-29188

Weaknesses

No CWEs

Credits