# CVE-2026-69246: Guzzle: Noncanonical host can bypass host-based checks

> Attackers can bypass host-based security checks in Guzzle by using noncanonical host formats, allowing access to restricted internal hosts and reading sensitive data.

- **Severity:** High 7.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/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:** 3 Aug 2026
- **Updated:** 4 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-69246, GHSA-v5mv-p594-2x33, MINI-3hpr-xgqh-ggg2, MINI-4w97-j53p-c939, MINI-7pv7-4m4g-q3hx, MINI-m58m-8267-xh7g, MINI-m7hv-q2pw-v255, MINI-mpqr-4mmq-r473, UBUNTU-CVE-2026-69246

## What is CVE-2026-69246?

CVE-2026-69246 is a high-severity server-side request forgery vulnerability in guzzle, published on 3 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Guzzle is an extensible PHP HTTP client. Prior to 7.15.2 and 8.0.1, Guzzle gives a transport the request URI as text and supplies the Host header separately. The cURL handlers set CURLOPT_URL to the URI exactly as written and push that Host into CURLOPT_HTTPHEADER; StreamHandler does the same through fopen(). libcurl then parses the authority itself, percent-decoding it and, on an IDN-capable build, applying IDNA mapping, and uses the result to resolve, connect, name the TLS peer and address a proxy CONNECT, while the supplied Host suppresses the aligned one libcurl would have generated. For a URI host written as 127.0.0.%31, filter_var() rejects the host as an IP literal, yet libcurl decodes it to 127.0.0.1 and reaches loopback with no DNS lookup while the server receives Host: 127.0.0.%31. An attacker who influences a fetched URI can therefore reach a host the application's checks excluded and read whatever the host exposes of the response. The same divergence moves Guzzle's own decisions onto a spelling the transport does not use: no_proxy selects proxy routing from the literal host, and RedirectMiddleware decides from it whether to strip Authorization and Cookie. Exploitation requires the application to build a request URI from untrusted input and to make a host decision before handing it to Guzzle. This issue is fixed in versions 7.15.2 and 8.0.1.

Weakness: CWE-941 (Incorrectly Specified Destination in a Communication Channel), CWE-918 (Server-Side Request Forgery), CWE-436 (Interpretation Conflict), CWE-180 (Incorrect Behavior Order: Validate Before Canonicalize)

## Which versions are affected by CVE-2026-69246?

4 open source packages ship an affected version, including guzzlehttp/guzzle.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `guzzlehttp/guzzle` | Packagist | All versions | 7.15.2 |
| `guzzlehttp/guzzle` | Packagist | All versions | 7.15.2 |
| `guzzlehttp/guzzle` | Packagist | From 8.0.0 | 8.0.1 |
| `guzzlehttp/guzzle` | Packagist | From 8.0.0 | 8.0.1 |

## How do I fix CVE-2026-69246?

Upgrade guzzlehttp/guzzle to a fixed version for your release line: 7.15.2 or 8.0.1.

## Is CVE-2026-69246 being exploited?

There is no known exploitation of CVE-2026-69246 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-69246 and fix it if it is affected.

What it is: CVE-2026-69246 is a high-severity server-side request forgery vulnerability in guzzle, published on 3 Aug 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-2026-69246 in the wild and no public exploit code.

Affected packages and fixed versions:
- guzzlehttp/guzzle (Packagist): affected all versions; fixed in 7.15.2
- guzzlehttp/guzzle (Packagist): affected all versions; fixed in 7.15.2
- guzzlehttp/guzzle (Packagist): affected from 8.0.0; fixed in 8.0.1
- guzzlehttp/guzzle (Packagist): affected from 8.0.0; fixed in 8.0.1

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-2026-69246/ (Markdown: https://insights.sbomify.com/CVE-2026-69246/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-69246
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-69246
- OSV: https://osv.dev/vulnerability/CVE-2026-69246

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-69246/
Summaries are generated and may contain mistakes; the official description above is the record.