ImproveSEO <= 2.0.11 - Unauthenticated Arbitrary File Upload Leading to Remote Code Execution

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-16618
StatePUBLISHED
AssignerWPScan
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-08-04 07:16:30 UTC
Updated2026-08-04 18:16:47 UTC
DescriptionThe Improve SEO WordPress plugin through 2.0.11 does not properly validate uploaded files, checking only the file content type while writing the file with the attacker-supplied extension into a publicly accessible directory, allowing unauthenticated users to upload executable PHP files and achieve remote code execution.

Risk And Classification

Primary CVSS: v3.1 9.8 CRITICAL from ADP

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Problem Types: CWE-434 | CWE-434 Unrestricted Upload of File with Dangerous Type | CWE-434 CWE-434 Unrestricted Upload of File with Dangerous Type

VersionSourceTypeScoreSeverityVector
3.1ADPDECLARED9.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
3.1134c704f-9b21-4f2e-91b3-4a467353bcc0Secondary9.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Unknown Improve SEO affected 2.0.11 semver Not specified

References

ReferenceSourceLinkTags
wpscan.com/vulnerability/3754d4c0-1b67-49a4-a29a-7169446638d1 [email protected] wpscan.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: João Ramos Maciel (en)

CNA: WPScan (en)

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report