# CVE-2026-54673: electron-updater: Cross-origin redirect leaks `PRIVATE-TOKEN` and mixed-case `Authorization` credentials in `builder-util-runtime`

> An attacker can steal GitLab PRIVATE-TOKEN and mixed-case Authorization credentials via cross-origin redirects in the Electron updater library.

- **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 30 Jun 2026
- **Updated:** 1 Jul 2026
- **Also known as:** GHSA-p2f4-r6v6-j797

## What is CVE-2026-54673?

CVE-2026-54673 is a high-severity vulnerability in electron-userland builder-util-runtime, published on 30 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

electron-updater allows for automatic updates for Electron apps. Prior to 9.7.0, the HTTP redirect handler (HttpExecutor.prepareRedirectUrlOptions) only stripped a credential header whose key string matched exactly lowercase "authorization", exposing credentials. Other credential-bearing headers — most notably PRIVATE-TOKEN (used by GitLab's personal access token flow) and mixed-case Authorization (used by GitLab's Bearer/OAuth flow) — were not stripped and could be forwarded to an attacker-controlled cross-origin redirect destination. This issue has been fixed in version 9.7.0.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2026-54673?

2 open source packages ship an affected version, including builder-util-runtime. It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `builder-util-runtime` | npm | All versions | 9.7.0 |
| `builder-util-runtime` | npm | All versions | 9.7.0 |

Products: Electron Builder-Util-Runtime, Electron Electron-Builder.

## How do I fix CVE-2026-54673?

Upgrade builder-util-runtime to 9.7.0 or later.

## Is CVE-2026-54673 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54673 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-54673 and fix it if it is affected.

What it is: CVE-2026-54673 is a high-severity vulnerability in electron-userland builder-util-runtime, published on 30 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54673 exists.

Affected packages and fixed versions:
- builder-util-runtime (npm): affected all versions; fixed in 9.7.0
- builder-util-runtime (npm): affected all versions; fixed in 9.7.0

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-2026-54673/ (Markdown: https://insights.sbomify.com/CVE-2026-54673/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-54673
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-54673
- OSV: https://osv.dev/vulnerability/CVE-2026-54673

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-54673/
Summaries are generated and may contain mistakes; the official description above is the record.