CVE-2026-33731 is a medium-severity (CVSS 6.5) CWE-345 vulnerability in wwbn/avideo. A fix is available for wwbn/avideo — see the affected versions and patch details below.
AVideo has an Authorize.Net Webhook Signature Bypass that Enables Wallet Balance Inflation via Forged Payment Data
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-33731.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-33731 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 376,715 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
wwbn/avideoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
WWBN AVideo is an open source video platform. In versions prior to 29.0, the Authorize.Net webhook handler at plugin/AuthorizeNet/webhook.php contains a signature verification bypass that allows an attacker to forge webhook requests with arbitrary payment amounts and target user IDs. By supplying a valid transaction ID from a small legitimate purchase, the attacker bypasses signature validation and credits arbitrary wallet balances to any user account via attacker-controlled payload fields. Three flaws combine into an exploit chain: signature bypass via OR logic (webhook.php:33), payload values override API-fetched values (AuthorizeNet.php:169-171, webhook.php:44-48) and a missing approval check (webhook.php:61-75). By forging payment metadata, an attacker can credit arbitrary amounts to any user's wallet without a corresponding payment and include a plans_id to activate premium subscriptions (webhook.php:86-134), enabling free access to all paid and premium content and causing direct revenue loss to the platform owner. This issue has been fixed in version 29.0.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | wwbn/avideo | all versions | 29.0composer require wwbn/avideo:^29.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for wwbn/avideo, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update wwbn/avideo to 29.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33731 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-33731 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-33731. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-33731 in your dependencies?
O3 Security finds CVE-2026-33731 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.