# CVE-2026-15075: Information disclosure in Eclipse Vert.x

> Attackers can steal sensitive headers like cookies and tokens when Vert.x clients follow cross-origin redirects due to missing origin checks.

- **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Jul 2026
- **Updated:** 14 Jul 2026
- **Also known as:** CLEANSTART-2026-BZ49747, CLEANSTART-2026-JF57527, CLEANSTART-2026-SB90321, CLEANSTART-2026-ZV89277

## What is CVE-2026-15075?

CVE-2026-15075 is a high-severity vulnerability in Eclipse Vert.x, published on 14 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In Eclipse Vert.x versions up to and including 4.5.29 (4.x branch) and 5.1.4 (5.x branch), DefaultRedirectHandler (vertx-core) propagates all request headers as-is across cross-origin HTTP 30x redirects. Only Content-Length is stripped; no origin comparison (scheme, host, port) is performed before copying headers to the redirect target.
As a result, credential headers, including Authorization, Cookie, Proxy-Authorization, and arbitrary custom headers such as X-API-Token, are forwarded to the redirect destination without the caller's knowledge.

An attacker who can cause a Vert.x HttpClient to issue a request that is redirected to an attacker-controlled host (for example, by supplying a URL to a webhook dispatcher, image proxy, or microservice URL fetcher) can capture bearer tokens, basic-auth credentials, session cookies, and API keys attached to the original request.

Weakness: CWE-346 (Origin Validation Error), CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2026-15075?

It affects 1 product.


Products: Eclipse Vert.x.

## How do I fix CVE-2026-15075?

Upgrade to a fixed version.

## Is CVE-2026-15075 being exploited?

There is no known exploitation of CVE-2026-15075 in the wild and no public exploit code.

## Other vulnerabilities in Eclipse Vert.x

- [CVE-2019-17640](https://insights.sbomify.com/CVE-2019-17640/): Path Traversal in Eclipse Vert (critical 9.8)
- [CVE-2018-12542](https://insights.sbomify.com/CVE-2018-12542/): Eclipse Vert.x does not properly neutralize '' (forward slashes) sequences that can resolve to an external location (critical 9.8)
- [CVE-2018-12544](https://insights.sbomify.com/CVE-2018-12544/): Moderate severity vulnerability that affects io.vertx:vertx-core (critical 9.8)
- [CVE-2026-102469](https://insights.sbomify.com/CVE-2026-102469/): Deserialization in Eclipse Vert.x (critical 9.2)
- [CVE-2018-12540](https://insights.sbomify.com/CVE-2018-12540/): High severity vulnerability that affects io.vertx:vertx-web (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-15075 and fix it if it is affected.

What it is: CVE-2026-15075 is a high-severity vulnerability in Eclipse Vert.x, published on 14 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-15075 in the wild and no public exploit code.

Affected product: Eclipse Vert.x. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-15075/ (Markdown: https://insights.sbomify.com/CVE-2026-15075/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-15075
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-15075
- OSV: https://osv.dev/vulnerability/CVE-2026-15075

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-15075/
Summaries are generated and may contain mistakes; the official description above is the record.