Answer in brief
CVE-2026-84120 records a Unknown severity vulnerability in Use-after-free in the Audio/Video component. The current sources do not mark it as known exploited. Affected software not mapped in the current feed; confirm the named product and version against your inventory.
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.
Affected software not mapped in the current feed; confirm the named product and version against your inventory.
Published upstream
Sep 1, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 1, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 1, 2026
Use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, and Firefox ESR 153.2.
Quoted source text, attributed separately from HOL analysis.