CVE-2026-55826 json
Customer Order Data Exposed via Unauthenticated gtm_server_side_order_id Cookie Manipulation in GTM Server Side WordPress Plugin
published 4mo ago modified 13d ago also EUVD-2026-108976 , GHSA-j5j2-gr8c-8rvf
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository stape-io/gtm-server-side-wordpress-plugin. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 8.7
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 27%
- public exploits
- 0
- none known
Summary
The GTM Server Side plugin by stape.io implements server-side tracking on WordPress websites. From version 2.0.0 to before version 2.1.48, the WooCommerce purchase event tracking mechanism allows an unauthenticated attacker to trigger the rendering of another customer's full order data — including personally identifiable information (PII) — into the page's JavaScript dataLayer. This issue has been patched in version 2.1.48.
Patch / fix
Is CVE-2026-55826 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 13d ago
Exploit prediction
0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- stape-io gtm-server-side-wordpress-plugin
Classification
- Weakness
-
- CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
References
- github.com /stape-io/gtm-server-side-wordpress-plugin/commit/702898f57772279ca63d3f800336c1803103ea41
- github.com /stape-io/gtm-server-side-wordpress-plugin/commit/9ff46a050028c40fad5416f2fa35be574c823434
-
github.com
/stape-io/gtm-server-side-wordpress-plugin/security/advisories/GHSA-j5j2-gr8c-8rvf
advisory
- github.com /stape-io/gtm-server-side-wordpress-plugin/releases/tag/2.1.48
- github.com /stape-io/gtm-server-side-wordpress-plugin/tree/v2.1.48
- github.com /stape-io/gtm-server-side-wordpress-plugin/tree/v2.1.47
Sources
- CVE List CVE-2026-55826
- NVD CVE-2026-55826
- Maintainer advisory GHSA-j5j2-gr8c-8rvf
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of stape-io/gtm-server-side-wordpress-plugin published their own advisory on GitHub. Reviewed sources take precedence over it.