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CWE-345Weakness · CWE-345

CVE-2026-48799

HIGH · 7.7 CVSS v3.1 Published 2026-07-15
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
83/100
Remediation priority · High
Remotely reachable Zero-click 5 weeks old

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
Postiz is an AI social media scheduling tool. Prior to 2.21.8, Postiz fails to verify Nowpayments IPN callback authenticity against the payment provider shared secret and reads the target subscription identifier from the untrusted request body, allowing a low-privileged account to grant arbitrary organizations lifetime PRO subscriptions without payment. This issue is fixed in version 2.21.8.

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

Postiz fails to validate the authenticity of Nowpayments IPN callbacks by verifying the shared secret, and incorrectly trusts the subscription identifier from the untrusted request body instead of a trusted source. This allows a low-privileged authenticated user to send crafted IPN requests that grant arbitrary organizations lifetime PRO subscriptions without actual payment.

MitigationUpgrade to Postiz version 2.21.8 or later, which implements proper IPN signature verification using the payment provider's shared secret and validates subscription data from trusted sources.

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

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
Low
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/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. Identify Postiz installation and version
    Check the installed Postiz version by inspecting the package.json file, docker image tag, or running 'postiz --version' if CLI available. Compare against the affected range (versions before 2.21.8).
    Affected if Postiz version is installed and is lower than 2.21.8
  2. Locate Nowpayments configuration
    Search for Nowpayments integration settings in the Postiz configuration files, environment variables (look for NOWPAYMENTS_API_KEY, NOWPAYMENTS_IPN_SECRET, or similar), or admin dashboard payment settings.
    Affected if Nowpayments is configured as a payment provider in the Postiz instance
  3. Verify IPN callback endpoint exists
    Inspect the Postiz API routes or server configuration for IPN (Instant Payment Notification) endpoints related to Nowpayments. Check routes such as /api/ipn/nowpayments or similar paths.
    Affected if The Nowpayments IPN callback endpoint is exposed and accessible
  4. Check for signature validation in IPN handler
    Review the source code of the IPN callback handler (if accessible) to verify whether it validates the shared secret/signature from Nowpayments before processing subscription data.
    Affected if The IPN handler does not verify the Nowpayments shared secret signature before trusting the request body

A Postiz instance is affected if it runs a version lower than 2.21.8 with Nowpayments configured as the payment provider and the IPN callback endpoint accepts requests without signature validation.

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
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade to Postiz version 2.21.8 or later, which implements proper IPN signature verification using the payment provider's shared secret and validates subscription data from trusted sources.

Recommended fix High confidence

2.21.8

  1. 1. Identify the current version of Postiz running in your environment
  2. 2. Back up your Postiz database and configuration files
  3. 3. Upgrade Postiz to version 2.21.8 or later
  4. 4. Verify the upgrade was successful by checking the version number
  5. 5. Test the Nowpayments IPN callback functionality to confirm the fix is working

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

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,640
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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-2026-48799 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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