# CVE-2026-4525: Vault Token Leaked to Backends via Authorization: Bearer Passthrough Header

> Attackers can steal Vault tokens if the Authorization header passthrough is enabled, exposing sensitive credentials to backend plugins.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Apr 2026
- **Updated:** 15 Jul 2026
- **Also known as:** BIT-vault-2026-4525, GHSA-72gw-fmmr-c4r4, GO-2026-5199, MINI-5wqq-hrmf-2h3f, MINI-pfj3-7m8v-mhgw

## What is CVE-2026-4525?

CVE-2026-4525 is a high-severity vulnerability in Hashicorp Vault, published on 17 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

If a Vault auth mount is configured to pass through the "Authorization" header, and the "Authorization" header is used to authenticate to Vault, Vault forwarded the Vault token to the auth plugin backend. Fixed in 2.0.0, 1.21.5, 1.20.10, and 1.19.16.

Weakness: CWE-201 (Insertion of Sensitive Information Into Sent Data)

## Which versions are affected by CVE-2026-4525?

4 open source packages ship an affected version, including github.com/hashicorp/vault and vault. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/hashicorp/vault` | Go | From 0.11.2 | None |
| `github.com/hashicorp/vault` | Go | From 0.11.2 to 1.21.4 | None |
| `github.com/hashicorp/vault` | Go | From 0.11.2 to 1.21.4 | None |
| `vault` | Bitnami | From 0.10.0 | 2.0.0 |

Products: Hashicorp Vault.

## How do I fix CVE-2026-4525?

Upgrade to a fixed version.

## Is CVE-2026-4525 being exploited?

There is no known exploitation of CVE-2026-4525 in the wild and no public exploit code.

## Other vulnerabilities in Hashicorp Vault

- [CVE-2020-35192](https://insights.sbomify.com/CVE-2020-35192/): Hardcoded credentials in n/a (critical 9.8)
- [CVE-2020-12757](https://insights.sbomify.com/CVE-2020-12757/): Improper Input Validation in HashiCorp Vault (critical 9.8)
- [CVE-2025-6000](https://insights.sbomify.com/CVE-2025-6000/): Arbitrary Remote Code Execution via Plugin Catalog Abuse (critical 9.1)
- [CVE-2022-40186](https://insights.sbomify.com/CVE-2022-40186/): HashiCorp Vault vulnerable to incorrect metadata access (critical 9.1)
- [CVE-2022-36129](https://insights.sbomify.com/CVE-2022-36129/): Missing authorization in n/a (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-4525 and fix it if it is affected.

What it is: CVE-2026-4525 is a high-severity vulnerability in Hashicorp Vault, published on 17 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-4525 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/hashicorp/vault (Go): affected from 0.11.2; no fix listed
- github.com/hashicorp/vault (Go): affected from 0.11.2 up to 1.21.4; no fix listed
- github.com/hashicorp/vault (Go): affected from 0.11.2 up to 1.21.4; no fix listed
- vault (Bitnami): affected from 0.10.0; fixed in 2.0.0

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-2026-4525/ (Markdown: https://insights.sbomify.com/CVE-2026-4525/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-4525
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-4525
- OSV: https://osv.dev/vulnerability/CVE-2026-4525

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-4525/
Summaries are generated and may contain mistakes; the official description above is the record.