# CVE-2026-42033: Axios: Prototype Pollution Gadgets - Response Tampering, Data Exfiltration, and Request Hijacking

> Attackers can tamper with responses or hijack requests if prototype pollution exists, exposing credentials and modifying data.

- **Severity:** High 7.4 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Apr 2026
- **Updated:** 10 Sep 2026
- **Also known as:** CLEANSTART-2026-NG59834, CLEANSTART-2026-RW51509, DEBIAN-CVE-2026-42033, ECHO-cddf-3336-1340, GHSA-pf86-5x62-jrwf, MINI-33v5-rx48-6v7q, MINI-5cpr-7jmv-2qx8, MINI-5x4x-rxxf-6vrx, MINI-6grg-mg2c-9q38, MINI-7pjh-pp7r-56pw, MINI-7w9w-q4gr-9222, MINI-8v9w-g9jf-98f5, MINI-8wr8-6qjq-m3vf, MINI-93f6-j28x-j2jw, MINI-chvp-vcpw-x3cp, MINI-jmpm-mxj4-8f5j, MINI-mrp4-p8f9-c2jc, MINI-p2xm-mxp3-7cqf, MINI-qm97-mxwr-3wr8, MINI-v9f6-vh57-x5r2, MINI-wj2x-vm77-rghv, MINI-wxmp-542w-p844, MINI-x6fg-55p4-c689, MINI-xvr6-47g9-7j7m, ROOT-APP-NPM-CVE-2026-42033, UBUNTU-CVE-2026-42033

## What is CVE-2026-42033?

CVE-2026-42033 is a high-severity unsafe deserialization vulnerability in axios, published on 24 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Axios is a promise based HTTP client for the browser and Node.js. Prior to 1.15.1 and 0.31.1, when Object.prototype has been polluted by any co-dependency with keys that axios reads without a hasOwnProperty guard, an attacker can (a) silently intercept and modify every JSON response before the application sees it, or (b) fully hijack the underlying HTTP transport, gaining access to request credentials, headers, and body. The precondition is prototype pollution from a separate source in the same process. This vulnerability is fixed in 1.15.1 and 0.31.1.

Weakness: CWE-915 (Improperly Controlled Modification of Dynamically-Determined Object Attributes), CWE-1321 (Improperly Controlled Modification of Object Prototype Attributes)

## Which versions are affected by CVE-2026-42033?

4 open source packages ship an affected version, including axios. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `axios` | npm | All versions | 0.31.1 |
| `axios` | npm | All versions | 0.31.1 |
| `axios` | npm | From 1.0.0 | 1.15.1 |
| `axios` | npm | From 1.0.0 | 1.15.1 |

Products: Axios Axios.

## How do I fix CVE-2026-42033?

Upgrade axios to a fixed version for your release line: 0.31.1 or 1.15.1.

## Is CVE-2026-42033 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42033 exists.

## Other vulnerabilities in axios

- [CVE-2026-44494](https://insights.sbomify.com/CVE-2026-44494/): Axios: Full Man-in-the-Middle via Prototype Pollution Gadget in `config.proxy` (high 8.7)
- [CVE-2026-44492](https://insights.sbomify.com/CVE-2026-44492/): axios's shouldBypassProxy does not recognize IPv4-mapped IPv6 addresses, allowing NO_PROXY bypass (incomplete fix for CVE-2025-62718) (high 8.6)
- [CVE-2026-67320](https://insights.sbomify.com/CVE-2026-67320/): axios before 0.33.0 Prototype Pollution via Node HTTP adapter (high 8.3)
- [CVE-2026-44487](https://insights.sbomify.com/CVE-2026-44487/): Axios: Proxy-Authorization Credential Leak to Origin Server Across HTTP-to-HTTPS Redirect in Axios Node.js HTTP Adapter (high 8.2)
- [CVE-2025-27152](https://insights.sbomify.com/CVE-2025-27152/): Possible SSRF and Credential Leakage via Absolute URL in axios Requests (high 7.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-42033 and fix it if it is affected.

What it is: CVE-2026-42033 is a high-severity unsafe deserialization vulnerability in axios, published on 24 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42033 exists.

Affected packages and fixed versions:
- axios (npm): affected all versions; fixed in 0.31.1
- axios (npm): affected all versions; fixed in 0.31.1
- axios (npm): affected from 1.0.0; fixed in 1.15.1
- axios (npm): affected from 1.0.0; fixed in 1.15.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-42033/ (Markdown: https://insights.sbomify.com/CVE-2026-42033/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-42033
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-42033
- OSV: https://osv.dev/vulnerability/CVE-2026-42033

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-42033/
Summaries are generated and may contain mistakes; the official description above is the record.