# CVE-2023-51651: Potential URI resolution path traversal in the AWS SDK for PHP

> Attackers can access arbitrary S3 objects via path traversal in AWS SDK for PHP when handling specific object keys.

- **Severity:** Medium 6.0 (`CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 22 Dec 2023
- **Updated:** 2 Aug 2024
- **Also known as:** CLSA-2026-1769993567, UBUNTU-CVE-2023-51651

## What is CVE-2023-51651?

CVE-2023-51651 is a medium-severity path traversal vulnerability in aws-sdk-php, published on 22 Dec 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

AWS SDK for PHP is the Amazon Web Services software development kit for PHP. Within the scope of requests to S3 object keys and/or prefixes containing a Unix double-dot, a URI path traversal is possible. The issue exists in the `buildEndpoint` method in the RestSerializer component of the AWS SDK for PHP v3 prior to 3.288.1. The `buildEndpoint` method relies on the Guzzle Psr7 UriResolver utility, which strips dot segments from the request path in accordance with RFC 3986. Under certain conditions, this could lead to an arbitrary object being accessed. This issue has been patched in version 3.288.1.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2023-51651?

It affects 1 product.


Products: Amazon Aws Software Development Kit.

## How do I fix CVE-2023-51651?

Upgrade to a fixed version.

## Is CVE-2023-51651 being exploited?

There is no known exploitation of CVE-2023-51651 in the wild and no public exploit code.

## Other vulnerabilities in aws-sdk-php

- [CVE-2018-19981](https://insights.sbomify.com/CVE-2018-19981/): Information disclosure in n/a (high 7.2)
- [CVE-2026-19642](https://insights.sbomify.com/CVE-2026-19642/): Out-of-bounds write in the Base64 decoder in Amazon aws-sdk-cpp (medium 6.0)
- [CVE-2026-19643](https://insights.sbomify.com/CVE-2026-19643/): Out-of-bounds read in the Base64 decoder in Amazon aws-sdk-cpp on signed-char platforms (medium 6.0)
- [CVE-2022-4725](https://insights.sbomify.com/CVE-2022-4725/): AWS SDK XML Parser XpathUtils.java XpathUtils server-side request forgery (medium 5.5)
- [CVE-2022-2582](https://insights.sbomify.com/CVE-2022-2582/): Exposure of unencrypted plaintext hash in github.com/aws/aws-sdk-go (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-51651 and fix it if it is affected.

What it is: CVE-2023-51651 is a medium-severity path traversal vulnerability in aws-sdk-php, published on 22 Dec 2023. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-51651 in the wild and no public exploit code.

Affected product: aws-sdk-php. 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-2023-51651/ (Markdown: https://insights.sbomify.com/CVE-2023-51651/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-51651
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-51651
- OSV: https://osv.dev/vulnerability/CVE-2023-51651

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-51651/
Summaries are generated and may contain mistakes; the official description above is the record.