CVE-2025-3889Network attack vector

Unauthenticated order-total reduction via negative quantities

Published May 1, 2025 · Updated Apr 8, 2026

Authorization bypass in Simple Shopping Cart 5.1.3 and earlier allows remote attackers to reduce order totals through negative quantities. The process_payment_data path accepts a user-controlled cart key and applies a negative quantity without validating that the value is nonnegative. No authentication is required, but Manual Checkout must be enabled; PayPal and Stripe reject negative quantities, limiting the effect to underpriced manual orders.

CVSS severity5.3
Medium
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authorization bypass in Simple Shopping Cart 5.1.3 and earlier allows remote attackers to reduce order totals through negative quantities. The process_payment_data path accepts a user-controlled cart key and applies a negative quantity without validating that the value is nonnegative. No authentication is required, but Manual Checkout must be enabled; PayPal and Stripe reject negative quantities, limiting the effect to underpriced manual orders.

The record

CVE
CVE-2025-3889
Published
May 1, 2025
Updated
Apr 8, 2026
Vendor
Tips and Tricks HQ
Product
Simple Shopping Cart
Classifications
CWE-639, T1565.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 1, 2025CVE publishedPublication date reported by the CVE source.
  2. Apr 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=5.1.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Tips and Tricks HQ · Simple Shopping Cartversion=0 <=5.1.3

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
5.3WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key
T1565.003Runtime Data Manipulation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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