Answer in brief
CVE-2026-16618 records a Critical severity (CVSS 9.8) vulnerability in ImproveSEO <= 2.0.11 - Unauthenticated Arbitrary File Upload Leading to Remote Code Execution. The current sources do not mark it as known exploited. The current feed maps Unknown/Improve SEO (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Unknown/Improve SEO (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Unknown/Improve SEOgeneric | 0 | Not reported |
Published upstream
Aug 4, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 4, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 4, 2026
The 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.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-16618 records a Critical severity (CVSS 9.8) vulnerability in ImproveSEO <= 2.0.11 - Unauthenticated Arbitrary File Upload Leading to Remote Code Execution. The current sources do not mark it as known exploited. The current feed maps Unknown/Improve SEO (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Unknown/Improve SEO (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Unknown/Improve SEOgeneric | 0 | Not reported |
Published upstream
Aug 4, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 4, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 4, 2026
The 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.
Quoted source text, attributed separately from HOL analysis.