Answer in brief
CVE-2018-20677 records a Medium severity (CVSS 6.1) vulnerability in bootstrap Cross-site Scripting vulnerability. The current sources do not mark it as known exploited. The current feed maps org.webjars:bootstrap (maven), bootstrap (npm), bootstrap-sass (npm), bootstrap (nuget) and additional mapped packages. 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 6.1. 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 org.webjars:bootstrap (maven), bootstrap (npm), bootstrap-sass (npm), bootstrap (nuget) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| org.webjars:bootstrapmaven | >=0 <3.4.0 | 3.4.0 |
| bootstrapnpm | >=0 <3.4.0 | 3.4.0 |
| bootstrap-sassnpm | >=0 <3.4.0 | 3.4.0 |
| bootstrapnuget | >=0 <3.4.0 | 3.4.0 |
| twbs/bootstrappackagist | >=0 <3.4.0 | 3.4.0 |
| bootstraprubygems | >=0 <3.4.0 | 3.4.0 |
| bootstrap-sassrubygems | >=0 <3.4.0 | 3.4.0 |
Published upstream
Jan 17, 2019
Evidence: source:osv:source_dates:source-dates:recordSource modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:recordFirst seen by HOL
Aug 7, 2026
In Bootstrap before 3.4.0, XSS is possible in the affix configuration target property.
Quoted source text, attributed separately from HOL analysis.