CVE-2026-79410 Overview
CVE-2026-79410 is an input validation flaw ([CWE-20]) in Webkul Bagisto v2.4.9, an open-source Laravel-based e-commerce platform. The vulnerability resides in the add-to-cart path, where the application fails to properly validate the quantity parameter. Authenticated attackers can manipulate this parameter to reduce their order total below the legitimate price of shippable goods. The flaw enables business logic abuse against merchants running the affected version, resulting in financial loss and inventory manipulation.
Critical Impact
Authenticated attackers can purchase physical goods at fraudulent prices by tampering with cart quantity values, directly impacting merchant revenue and inventory integrity.
Affected Products
- Webkul Bagisto v2.4.9
- Deployments using the default add-to-cart controller and cart pricing logic
- Merchant storefronts shipping physical goods through the affected cart workflow
Discovery Timeline
- 2026-09-15 - CVE-2026-79410 published to the National Vulnerability Database (NVD)
- 2026-09-15 - Last updated in NVD database
Technical Details for CVE-2026-79410
Vulnerability Analysis
The defect is a business logic flaw driven by improper input validation on a client-supplied numeric parameter. Bagisto accepts the quantity value submitted by the authenticated user during the add-to-cart request without enforcing correct numeric bounds. When the value is manipulated (for example, to a fractional, zero, or negative representation), the pricing routine still processes the item as shippable while computing a total that falls below the legitimate goods price.
Because the request occurs over the network and requires only a low-privilege authenticated account, the barrier to exploitation is minimal. The impact centers on integrity of the order and confidentiality of pricing logic, without disrupting availability of the storefront.
Root Cause
The root cause is missing or insufficient server-side validation of the quantity field in the cart controller. Bagisto trusts the client-supplied value and passes it into price calculations. No enforcement of positive integer semantics, minimum order quantities, or price-floor checks occurs before the cart total is written to the session and eventually to the order record.
Attack Vector
An authenticated attacker registers or reuses an account on the storefront. The attacker intercepts the add-to-cart HTTP request using a proxy and modifies the quantity parameter to an unexpected value. The server accepts the tampered payload, applies flawed arithmetic, and permits checkout with an artificially reduced total for physical goods that must be shipped.
Full technical reproduction steps are documented in the researcher's writeup at GitHub CVE-2026-79410 Details. No verified proof-of-concept code is reproduced here.
Detection Methods for CVE-2026-79410
Indicators of Compromise
- Orders where the recorded line-item total is inconsistent with unit_price * quantity for shippable SKUs.
- Add-to-cart requests containing non-integer, zero, or negative quantity values in application logs.
- Completed orders with unusually low subtotals relative to shipping cost or product weight.
- Repeated cart modifications from a single authenticated account preceding a low-value checkout.
Detection Strategies
- Add server-side assertions that recompute expected totals at checkout and flag mismatches for review.
- Instrument the Bagisto cart controller to log the raw quantity payload alongside the resolved cart total.
- Correlate web server access logs for POST requests to the cart endpoint with subsequent order records that deviate from catalog pricing.
Monitoring Recommendations
- Monitor application logs for anomalous quantity parameter values submitted to the add-to-cart endpoint.
- Alert on completed orders whose totals fall below a configurable percentage of the sum of catalog list prices.
- Track per-account behavior for repeated cart tampering patterns and escalate accounts that trigger pricing anomalies.
How to Mitigate CVE-2026-79410
Immediate Actions Required
- Upgrade Webkul Bagisto beyond v2.4.9 once the vendor publishes a patched release addressing the quantity validation flaw.
- Apply strict server-side validation on the quantity parameter to accept only positive integers within a defined range.
- Recompute order totals server-side at checkout using authoritative catalog prices, ignoring client-supplied pricing hints.
- Audit recent orders for pricing anomalies and reverse or investigate transactions with implausible totals.
Patch Information
No vendor advisory or patched version is listed in the NVD entry at the time of publication. Consult the researcher's disclosure at GitHub CVE-2026-79410 Details and monitor the Webkul Bagisto release channel for a security fix. Apply the vendor patch as soon as it becomes available.
Workarounds
- Deploy a web application firewall (WAF) rule that rejects add-to-cart requests where quantity is not a positive integer.
- Enforce a checkout-time integrity check that fails the transaction if line_total != catalog_price * quantity.
- Restrict account registration and rate-limit cart operations to slow automated abuse attempts.
# Example WAF rule concept (ModSecurity) - review before deploying
SecRule ARGS:quantity "!@rx ^[1-9][0-9]{0,3}$" \
"id:1079410,phase:2,deny,status:400,\
msg:'Invalid cart quantity - CVE-2026-79410'"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.