{"id":"CVE-2026-56831","title":"Shopper is a Headless e-commerce Admin Panel","summary":"Shopper is a Headless e-commerce Admin Panel. Prior to 2.9.0, the /cpanel/discounts administrative interface accepts negative fixed_amount discount values, persists them in sh_discounts, and passes them through vendor/shopper/cart/src/Di…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","cwe":["CWE-20"],"vendor":"shopperlabs","product":"shopper","affected":["shopper < 2.9.0"],"patched":["shopper/framework 2.9.0"],"published":"2026-09-15","updated":"2026-09-16","sourceUpdated":"2026-09-16T15:17:38.200","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-56831","references":[{"url":"https://github.com/shopperlabs/shopper/commit/967e616281ded1a0050d9102858ecd7dd7f66a41","label":"security-advisories@github.com"},{"url":"https://github.com/shopperlabs/shopper/pull/528","label":"security-advisories@github.com"},{"url":"https://github.com/shopperlabs/shopper/releases/tag/v2.9.0","label":"security-advisories@github.com"},{"url":"https://github.com/shopperlabs/shopper/security/advisories/GHSA-5vf4-452p-jjhf","label":"security-advisories@github.com"},{"url":"https://github.com/shopperlabs/shopper/security/advisories/GHSA-5vf4-452p-jjhf","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://github.com/advisories/GHSA-5vf4-452p-jjhf"}],"tags":["nvd","cve.org","exploit-available","ghsa","composer"],"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-16T14:41:46.439666Z"},"aliases":["GHSA-5vf4-452p-jjhf"],"ecosystem":"composer","ingestedAt":"2026-09-12T00:03:49.069Z","epss":0.00406,"epssPercentile":0.34652,"slug":"CVE-2026-56831","body":"## Overview\n\nShopper is a Headless e-commerce Admin Panel. Prior to 2.9.0, the /cpanel/discounts administrative interface accepts negative fixed_amount discount values, persists them in sh_discounts, and passes them through vendor/shopper/cart/src/Discounts/DiscountCalculator.php and vendor/shopper/cart/src/Pipelines/Calculate.php without enforcing a positive-value invariant. Because the calculation subtracts discountTotal from the subtotal, a negative discount increases the resulting order total instead of reducing it. Malformed discount records can therefore cause incorrect pricing and financial data integrity failures, although the advisory does not establish a customer-facing exploitation path. This issue is fixed in version 2.9.0.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-56831)\n\nAffected packages:\n\n- `shopper/framework < 2.9.0`\n\nPatched in:\n\n- `shopper/framework 2.9.0`\n\nSource: https://github.com/advisories/GHSA-5vf4-452p-jjhf","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":204989,"id":"CVE-2026-56831","ts":1789570701754,"field":"exploit_available","old":"false","new":"true"}]}