CVE-2026-33143: OneUptime WhatsApp Webhook signature verification bypass

CVE-2026-33143 · Severity: high · CVSS 7.5 · Published 2026-03-20

OneUptime's WhatsApp notification service receives webhook events from Meta/WhatsApp to track message delivery status. An attacker can send fake webhook requests without authentication to manipulate delivery records, causing the system to incorrectly report that failed notifications were delivered, suppressing critical alerts and corrupting audit logs.

Technologies: Hackerbay Oneuptime, OneUptime. Vendors: Hackerbay, OneUptime.

Quick answers

Is CVE-2026-33143 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-33143 being exploited in the wild.
How severe is CVE-2026-33143?
High severity, with a CVSS score of 7.5, published 20 March 2026.
Which products and versions are affected?
OneUptime all versions up to and including 10.0.23; fixed in 10.0.34.
Is there a fix for CVE-2026-33143?
A patch was published on 2026-03-18: Fix available in version 10.0.34 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-33143 attacked?
It is attacked over the network, in a web application.
Am I affected by CVE-2026-33143?
Check whether you run Hackerbay Oneuptime or OneUptime at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The WhatsApp POST webhook endpoint (/notification/whatsapp/webhook) in OneUptime lacks HMAC signature verification for incoming Meta/WhatsApp events, accepting any unauthenticated payload. The vulnerability exists in App/FeatureSet/Notification/API/WhatsApp.ts (lines 372–430), where the code processes webhook entries without checking the X-Hub-Signature-256 header. The codebase already implements correct signature validation for Slack webhooks, demonstrating this is a known pattern the developers omitted for WhatsApp. An unauthenticated remote attacker can forge delivery status updates, inject arbitrary messages, and manipulate notification logs with network access to the endpoint. The fix is available in version 10.0.34.

Affected products

  • OneUptime OneUptime all versions up to and including 10.0.23; fixed in 10.0.34

Identifiers

  • CVE-2026-33143
  • GHSA-g5ph-f57v-mwjc

Timeline

  • 2026-03-18: disclosed: Public advisory published
  • 2026-03-18: patched: Fix available in version 10.0.34

References

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