CVE-2026-21129: Samsung Checkout improper input validation in activity

CVE-2026-21129 · Severity: info · Published 2026-10-12

Samsung Checkout is a mobile payment application used to process transactions on Samsung devices. A flaw in its credit card registration component allows local attackers to launch arbitrary activities with Checkout's elevated privileges, potentially enabling unauthorized payment operations or data access. A patch is available in version 5.1.03.1 and later.

Technologies: Samsung Checkout. Vendors: Samsung.

Quick answers

Is CVE-2026-21129 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-21129 being exploited in the wild.
How severe is CVE-2026-21129?
Informational severity, published 12 October 2026.
Which products and versions are affected?
Samsung Checkout prior to 5.1.03.1.
Is there a fix for CVE-2026-21129?
Yes: fixed in 5.1.03.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-21129 attacked?
It is attacked with local access, in a web application.
Am I affected by CVE-2026-21129?
Check whether you run Samsung Checkout at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • Fixed in: 5.1.03.1

Technical details

Improper input validation in GuestCreditCardRegisterActivity allows local attackers to launch arbitrary activities with Samsung Checkout privileges. This requires local code execution on the device but does not require user interaction once achieved. The vulnerability is fixed in version 5.1.03.1 through improved input validation.

Affected products

  • Samsung Checkout prior to 5.1.03.1

Timeline

  • 2026-10-12: disclosed

References

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