CVE-2026-27064

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreHIGH confidence

Score 9.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-07-23. a secondary CVSS source baseline 9.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.1Exploit: None knownExposed: 0

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

Editor Arbitrary File Upload in Mailster <= 4.1.17 versions.

CVSS v3
9.1
EG Score
9.1(high)
EG Risk
41(Track)
EG Risk 41/100SSVC: 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
Severity91% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
20%
KEV
Not listed

Published

July 23, 2026

Last Modified

July 23, 2026

Advisory Details (1)

Auto-updated Jul 23, 2026
No patch confirmed yet.
generic

Arbitrary File Upload in WordPress Mailster Plugin - Patchstack

https://patchstack.com/database/wordpress/plugin/mailster/vulnerability/wordpress-mailster-plugin-4-1-17-arbitrary-file-upload-vulnerability?_s_id=cve

Vendor Advisories for CVE-2026-27064(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 29× in last 7d / 29× 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. 2026-07-28 20:53 UTCGHSA enrichment
  2. 2026-07-28 16:49 UTCEG score recompute
  3. 2026-07-28 16:49 UTCGHSA enrichment
  4. 2026-07-28 15:36 UTCEPSS rescore
  5. 2026-07-28 11:26 UTCGHSA enrichment
  6. 2026-07-28 07:23 UTCGHSA enrichment
  7. 2026-07-28 03:20 UTCGHSA enrichment
  8. 2026-07-27 23:17 UTCGHSA enrichment
  9. 2026-07-27 19:11 UTCGHSA enrichment
  10. 2026-07-27 15:07 UTCEG score recompute
  11. 2026-07-27 15:07 UTCGHSA enrichment
  12. 2026-07-27 10:27 UTCGHSA enrichment
  13. 2026-07-27 06:24 UTCGHSA enrichment
  14. 2026-07-27 02:19 UTCGHSA enrichment
  15. 2026-07-26 22:14 UTCGHSA enrichment
  16. 2026-07-26 18:11 UTCEG score recompute
  17. 2026-07-26 18:11 UTCGHSA enrichment
  18. 2026-07-26 14:54 UTCEPSS rescore
  19. 2026-07-26 14:54 UTCEPSS rescore
  20. 2026-07-26 13:50 UTCEG score recompute
  21. 2026-07-26 13:50 UTCGHSA enrichment
  22. 2026-07-26 09:46 UTCGHSA enrichment
  23. 2026-07-26 03:16 UTCEG score recompute
  24. 2026-07-26 03:16 UTCGHSA enrichment
  25. 2026-07-25 14:18 UTCEPSS rescore
Show 4 more
  1. 2026-07-25 14:17 UTCEPSS rescore
  2. 2026-07-24 14:17 UTCEPSS rescore
  3. 2026-07-23 11:48 UTCEG score recompute
  4. 2026-07-23 11:39 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-27064?
CVE-2026-27064 is a critical vulnerability published on July 23, 2026. Editor Arbitrary File Upload in Mailster <= 4.1.17 versions.
When was CVE-2026-27064 disclosed?
CVE-2026-27064 was first published in the National Vulnerability Database on July 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-27064 actively exploited?
CVE-2026-27064 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 80.0% of all scored CVEs.
What is the CVSS score of CVE-2026-27064?
CVE-2026-27064 has a CVSS v3 base score of 9.1 (NVD).
How do I remediate CVE-2026-27064?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-27064, 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-2026-27064

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