Order disruption via unauthenticated payment callback forgery
Published Sep 15, 2026 · Updated Sep 15, 2026
Improper payment callback validation in J2Store before 3.3.22, 4.0.22, or 4.1.7 allows remote attackers to fail arbitrary orders. The PayPal IPN listener accepts UNVERIFIED and other non-INVALID responses, disables peer verification, leaves its verdict unused, and skips the amount check when mc_gross is absent. Exploitation requires PayPal to be enabled and the storefront callback to be publicly reachable; forged requests can disrupt order processing and create refund, cancellation, and reprocessing work.
Summary
What happened
Improper payment callback validation in J2Store before 3.3.22, 4.0.22, or 4.1.7 allows remote attackers to fail arbitrary orders. The PayPal IPN listener accepts UNVERIFIED and other non-INVALID responses, disables peer verification, leaves its verdict unused, and skips the amount check when mc_gross is absent. Exploitation requires PayPal to be enabled and the storefront callback to be publicly reachable; forged requests can disrupt order processing and create refund, cancellation, and reprocessing work.
The record
- CVE
- CVE-2026-82189
- Published
- Sep 15, 2026
- Updated
- Sep 15, 2026
- Vendor
- J2Commerce
- Product
- J2Store
- Classifications
- T1565.001
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 15, 2026CVE publishedPublication date reported by the CVE source.
- Sep 15, 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.
- Affected versionversion=1.0.0-3.3.22
- Affected versionversion=4.0.0-4.0.22
- Affected versionversion=4.1.0-4.1.7
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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