Axios: Prototype Pollution Gadget in axios toFormData Options

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)

[ Description ]Official 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.

[ Fixes ]Fixes and patches

• axios 0.34.0Fixed version · GitHub Advisories · npm package axios: upgrade to 0.34.0 or later (affected >= 0.28.0, < 0.34.0)
• axios 1.20.0Fixed version · GitHub Advisories · npm package axios: upgrade to 1.20.0 or later (affected >= 1.15.1, < 1.20.0)

[ Advisories ]Government CERT advisories

• BSI CERT-Bund20 Oct 2026WID-SEC-2026-4056

  Atlassian products (Bamboo, Bitbucket, Confluence, Crucible, Fisheye and Jira): Multiple vulnerabilities Translated from German

  CVE-2026-13676CVE-2026-50750CVE-2026-53404+72 more CVEs
• CERT-FR16 Oct 2026CERTFR-2026-AVI-1336

  Multiple vulnerabilities in IBM products Translated from French

  Multiple vulnerabilities have been discovered in IBM products. Some of them allow an attacker to cause remote arbitrary code execution, privilege escalation and remote denial of service.

  CVE-2026-14671CVE-2026-11548CVE-2022-22950+490 more CVEs

[ Packages ]Affected open-source packages

• axios npmAffected >= 0.28.0, < 0.34.0 · fixed in 0.34.0 · GHSA-x97p-jq2g-jp4f
• axios npmAffected >= 1.15.1, < 1.20.0 · fixed in 1.20.0 · GHSA-x97p-jq2g-jp4f

[ References ]References

• github.com/axios/axios/commit/d19040bda7a8be2f82c3c6e1a5bc03917daee39a
• github.com/axios/axios/commit/d29be181f85f6fe93397a07b1f69606d9622637b
• github.com/axios/axios/pull/11141
• github.com/axios/axios/releases/tag/v0.34.0
• github.com/axios/axios/releases/tag/v1.20.0
• github.com/axios/axios/security/advisories/GHSA-x97p-jq2g-jp4f