Axios: Prototype Pollution Gadget in axios toFormData Options (CVE-2026-101909) | HOL Guard CVE

High · CVSS 8.3CVE-2026-101909

Axios: Prototype Pollution Gadget in axios toFormData Options

Answer in brief

CVE-2026-101909 records a High severity (CVSS 8.3) vulnerability in Axios: Prototype Pollution Gadget in axios toFormData Options. The current sources do not mark it as known exploited. The current feed maps axios/axios (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 28, 2026Updated Sep 28, 2026Source checked Sep 28, 2026First seen by HOL Sep 28, 2026Material review Sep 28, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.3
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 8.3. 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 scope and exposure questions

The current feed maps axios/axios (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
axios/axiosgeneric	>=1.15.1 <1.20.0 \|\| >=0.28.0 <0.34.0	1.20.0, 0.34.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for axios/axios.
Review the reported fix. Update axios/axios to 1.20.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 28, 2026

Sources and claim methodology

Upstream source description

Axios is a promise-based HTTP client for the browser and Node.js. From 0.28.0 until 0.34.0 and 1.15.1 until 1.20.0, ToFormData processes inherited serialization options and visitor properties supplied through prototype pollution. A separate same-process prototype-pollution flaw supplies inherited dots, indexes, metaTokens, maxDepth, visitor, or Blob values before object serialization. The inherited options alter toFormData field naming and data interpretation, maxDepth can force request failure, Blob changes value handling, and a polluted visitor can execute when an attacker already has the stronger ability to inject a function. Serialized field naming and data interpretation can change, maxDepth can cause request failure, Blob can alter value handling, and a polluted visitor can execute under the stronger function-injection primitive. This issue is fixed in versions 0.34.0 and 1.20.0.

Quoted source text, attributed separately from HOL analysis.