CVE-2023-51651 is a medium-severity (CVSS 6) Path Traversal vulnerability in aws/aws-sdk-php. O3 Security confirms whether CVE-2023-51651 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Potential URI resolution path traversal in the AWS SDK for PHP
Real-World Exposure
aws/aws-sdk-phpReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | aws/aws-sdk-php | all versions | 3.288.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for aws/aws-sdk-php. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update aws/aws-sdk-php to 3.288.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-51651 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2023-51651 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2023-51651. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-51651 in your dependencies?
O3 detects CVE-2023-51651 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.