CVE-2026-18051

CRITICALPre-NVD 10.010.0—
EchelonGraph scoreHIGH confidence

Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-19. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 10.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 5 sources updated this week
10.0EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 10.0Exploit: None knownExposed: 0

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

The W3 Total Cache WordPress plugin before 2.10.5 does not properly validate the request path it uses to build cache file names, allowing unauthenticated attackers to write a file into any existing directory on the server, inside or outside the web root, overwriting whatever occupies the target name. On Apache, the same flaw overwrites the site's .htaccess files, which breaks the site and can strip hardening rules that other security measures rely on.

CVSS v3
10.0
EG Score
10.0(high)
EG Risk
60(Track)
EG Risk 60/100SSVC: Track

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
Severity100% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
36%
KEV
Not listed

Published

August 19, 2026

Last Modified

August 19, 2026

Advisory Details (1)

Auto-updated Aug 19, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

W3 Total Cache < 2.10.5 – Unauthenticated Arbitrary Directory File Write and .htaccess Overwrite via Path Traversal in the Page Cache Key | CVE 2026-18051 | Plugin Vulnerabilities

https://wpscan.com/vulnerability/dc56cdd2-419b-4a64-9d2a-29dc7e79cb6d/

Vendor Advisories for CVE-2026-18051(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 20× in last 7d / 20× 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. 2026-08-21 04:04 UTCGHSA enrichment
  2. 2026-08-20 23:45 UTCEG score recompute
  3. 2026-08-20 23:45 UTCGHSA enrichment
  4. 2026-08-20 22:55 UTCEPSS rescore
  5. 2026-08-20 19:26 UTCGHSA enrichment
  6. 2026-08-20 15:07 UTCGHSA enrichment
  7. 2026-08-20 10:40 UTCGHSA enrichment
  8. 2026-08-20 06:21 UTCGHSA enrichment
  9. 2026-08-20 02:02 UTCGHSA enrichment
  10. 2026-08-19 21:43 UTCEG score recompute
  11. 2026-08-19 21:43 UTCGHSA enrichment
  12. 2026-08-19 17:24 UTCEG score recompute
  13. 2026-08-19 17:24 UTCGHSA enrichment
  14. 2026-08-19 17:03 UTCEPSS rescore
  15. 2026-08-19 16:52 UTCEG score recompute▲ 10.00
  16. 2026-08-19 16:52 UTCGHSA enrichment
  17. 2026-08-19 16:52 UTCMITRE cvelistV5CVSS v3 → 10 · severity → CRITICAL
  18. 2026-08-19 06:21 UTCNVD update
  19. 2026-08-19 06:18 UTCEG score recompute
  20. 2026-08-19 06:17 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-18051?
CVE-2026-18051 is a critical vulnerability published on August 19, 2026. The W3 Total Cache WordPress plugin before 2.10.5 does not properly validate the request path it uses to build cache file names, allowing unauthenticated attackers to write a file into any existing directory on the server, inside or outside the web root, overwriting whatever occupies the target…
When was CVE-2026-18051 disclosed?
CVE-2026-18051 was first published in the National Vulnerability Database on August 19, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-18051 actively exploited?
CVE-2026-18051 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 64.0% of all scored CVEs.
What is the CVSS score of CVE-2026-18051?
CVE-2026-18051 has a CVSS v3.1 base score of 10.0 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-18051?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-18051, 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

Explore the affected products and dependency analysis for CVE-2026-18051

Explore →

Is Your Infrastructure Affected by CVE-2026-18051?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs