Answer in brief
CVE-2026-42567 records a Medium severity vulnerability in Svelte: ReDoS in `<svelte:element>` Tag Validation. The current sources do not mark it as known exploited. The current feed maps svelte (npm), svelte (npm). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. 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 svelte (npm), svelte (npm). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| sveltenpm | >=5.51.5,<=5.55.6 | 5.55.7 |
| sveltenpm | >=5.51.5<=5.55.6 | Not reported |
Published upstream
May 14, 2026
Evidence: source:ghsa:source_dates:source-dates:recordSource modified
Jun 9, 2026
Evidence: source:ghsa:source_dates:source-dates:recordFirst seen by HOL
Jun 11, 2026
An internal regex in the Svelte runtime can take exponential time to test in `<svelte:element this={tag}></svelte:element>`. You are only vulnerable to this if you allow tags of unconstrained length. If your application only allows a predetermined list of tags or trims their length before passing them to `svelte:element`, you are safe.
Quoted source text, attributed separately from HOL analysis.