SmokescreenApplication · Stripe

CVE-2022-24825

MEDIUM · 5.3 CVSS v3.1 Published 2022-04-19
Fix available
A fix is available. Upgrade to 0.0.3 or later.
See remediation →
62/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Smokescreen is a simple HTTP proxy that fogs over naughty URLs. 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 appending a dot to the end of user-supplied URLs, or by providing input in a different letter case. Recommended to upgrade Smokescreen to version 0.0.3 or later.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The deny list feature in Smokescreen HTTP proxy can be bypassed by appending a trailing dot to URLs or by altering letter case, allowing attackers to access blocked external URLs despite the deny list protection. This is a case sensitivity and input normalization flaw in the URL validation logic.

MitigationUpgrade Smokescreen to version 0.0.3 or later, which contains the fix for this deny list bypass vulnerability.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
SmokescreenApplication
Affected:< 0.0.3

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Determine Smokescreen version
    Run the Smokescreen binary with version flag (e.g., --version, -v) or check the installed package version if deployed via package manager
    Affected if Version is below 0.0.3 (any version from initial release up to 0.0.2)
  2. Verify deny list is in use
    Check Smokescreen configuration files for deny_list or blocklist settings - look for YAML/JSON config files that define restricted domains or URL patterns
    Affected if Deny list feature is enabled and configured with blocking rules
  3. Test URL case sensitivity bypass
    Attempt to access a blocked domain using mixed-case letters (e.g., example.com vs ExAmPlE.com) through the proxy and observe if the deny list blocks it
    Affected if Requests with altered letter case bypass deny list rules when they should be blocked
  4. Test trailing dot bypass
    Attempt to access a blocked domain with a trailing dot (e.g., example.com.) through the proxy and observe if the deny list blocks it
    Affected if Requests with trailing dot bypass deny list rules when they should be blocked

Your environment is affected if Smokescreen version is below 0.0.3 AND the deny list feature is enabled with blocking rules.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 0.0.3 or later
Fixed in 0.0.3
Interim mitigation

Upgrade Smokescreen to version 0.0.3 or later, which contains the fix for this deny list bypass vulnerability.

Recommended fix Moderate confidence

0.0.3 or later

  1. 1. Identify the current version of Smokescreen currently deployed
  2. 2. Review the Smokescreen 0.0.3 release notes to understand changes
  3. 3. In a test/staging environment, upgrade Smokescreen to version 0.0.3
  4. 4. Verify that the deny list functionality works correctly with URLs containing trailing dots and mixed-case inputs
  5. 5. After validation, upgrade the production instance to version 0.0.3 or later

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Smokescreen Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing3.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,190
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,904.

Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2022-24825 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data