# Pay by paynow.pl <= 2.5.12 - Unauthenticated Sensitive Information Exposure via Cached Payment Methods

- **ID:** WPSEC-2026-2700
- **Plugin:** Pay by paynow.pl (`pay-by-paynow-pl`), https://wordpress.org/plugins/pay-by-paynow-pl/
- **Affected versions:** all versions before 2.5.13
- **Fixed in:** 2.5.13 (Update to 2.5.13 or later.)
- **Severity:** Low 3.7 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N)
- **Weakness:** CWE-524
- **Usage among sites WPSec scans:** plugin Low, affected versions Low (as of 2026-11-07)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/pay-by-paynow-pl
- **Fix released:** 2026-11-06
- **Published:** 2026-11-07
- **URL:** https://wpsec.com/vuln/WPSEC-2026-2700/

## Description

The Pay by paynow.pl plugin for WordPress is vulnerable to Sensitive Information Exposure via the cached checkout payment methods in all versions up to, and including, 2.5.12, due to the payment methods list returned by Paynow being stored in a site-wide transient keyed only by the signature key, currency and amount. That list can include a logged-in customer's saved card instruments, and the key does not include the current user. This makes it possible for unauthenticated attackers who open checkout with the same currency and cart amount while the cached entry is valid (up to 24 hours) to view another customer's saved card details (card name, brand, expiry date and instrument token).

## References

- https://wpsec.com/vuln/WPSEC-2026-2700/
- https://plugins.svn.wordpress.org/pay-by-paynow-pl/tags/2.5.13/
- https://wordpress.org/plugins/pay-by-paynow-pl/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-2700/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.