CVE-2026-18603

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreHIGH confidence

Score 6.5 from GitHub Security Advisory published 2026-08-09. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this weekElevated
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

The PiWeb Cancel order / Refund request for WooCommerce WordPress plugin before 1.3.4.34 does not have authorization or ownership checks when adding the contents of a previous order to the cart, allowing unauthenticated users to disclose the contents of other customers' orders, as well as to clear and repopulate a logged in user's cart via a crafted link.

CVSS v3
6.5
EG Score
6.5(high)
EG Risk
60(Attend)
EG Risk 60/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity65% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
13%
KEV
Not listed

Published

August 9, 2026

Last Modified

August 10, 2026

Advisory Details (1)

Auto-updated Aug 10, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

Cancel Order & Request Woocommerce < 1.3.4.34 – Unauthenticated Order Content Disclosure via Reorder AJAX Actions | CVE 2026-18603 | Plugin Vulnerabilities

https://wpscan.com/vulnerability/544a35ce-c858-4718-ab43-6e945de6f278/

Vendor Advisories for CVE-2026-18603(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 19× in last 7d / 36× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-20 05:32 UTCEG score recompute
  2. 2026-08-20 05:32 UTCGHSA enrichment
  3. 2026-08-19 17:03 UTCEPSS rescore
  4. 2026-08-19 07:03 UTCGHSA enrichment
  5. 2026-08-18 08:33 UTCEG score recompute
  6. 2026-08-18 08:33 UTCGHSA enrichment
  7. 2026-08-17 13:47 UTCEPSS rescore
  8. 2026-08-17 09:57 UTCEG score recompute
  9. 2026-08-17 09:56 UTCGHSA enrichment
  10. 2026-08-16 14:56 UTCEPSS rescore
  11. 2026-08-16 11:28 UTCEG score recompute
  12. 2026-08-16 11:28 UTCGHSA enrichment
  13. 2026-08-16 02:14 UTCEPSS rescore
  14. 2026-08-15 13:00 UTCEG score recompute
  15. 2026-08-15 13:00 UTCGHSA enrichment
  16. 2026-08-15 01:30 UTCEPSS rescore
  17. 2026-08-14 14:31 UTCEG score recompute
  18. 2026-08-14 14:31 UTCGHSA enrichment
  19. 2026-08-13 22:00 UTCEPSS rescore
  20. 2026-08-13 16:03 UTCGHSA enrichment
  21. 2026-08-12 17:34 UTCEG score recompute
  22. 2026-08-12 17:34 UTCGHSA enrichment
  23. 2026-08-12 13:50 UTCEPSS rescore
  24. 2026-08-11 19:05 UTCEG score recompute
  25. 2026-08-11 19:05 UTCGHSA enrichment
Show 11 more
  1. 2026-08-11 13:42 UTCEPSS rescore
  2. 2026-08-11 00:00 UTCEPSS rescore
  3. 2026-08-10 20:31 UTCEG score recompute
  4. 2026-08-10 20:31 UTCGHSA enrichment
  5. 2026-08-10 19:45 UTCEG score recompute▲ 6.50
  6. 2026-08-10 19:45 UTCGHSA enrichment
  7. 2026-08-10 19:44 UTCMITRE cvelistV5CVSS v3 → 6.5 · severity → MEDIUM
  8. 2026-08-09 13:46 UTCEPSS rescore
  9. 2026-08-09 06:23 UTCNVD update
  10. 2026-08-09 06:05 UTCEG score recompute
  11. 2026-08-09 06:05 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-18603?
CVE-2026-18603 is a medium vulnerability published on August 9, 2026. The PiWeb Cancel order / Refund request for WooCommerce WordPress plugin before 1.3.4.34 does not have authorization or ownership checks when adding the contents of a previous order to the cart, allowing unauthenticated users to disclose the contents of other customers' orders, as well as to clear…
When was CVE-2026-18603 disclosed?
CVE-2026-18603 was first published in the National Vulnerability Database on August 9, 2026, with the most recent update on August 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-18603 actively exploited?
CVE-2026-18603 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 87.0% of all scored CVEs.
What is the CVSS score of CVE-2026-18603?
CVE-2026-18603 has a CVSS v3.1 base score of 6.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-18603?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-18603, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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