GHSA-27qh-8cxx-2cr5 — aws/aws-sdk-php
GHSA-27qh-8cxx-2cr5 is a security vulnerability in aws/aws-sdk-php. A fix is available for aws/aws-sdk-php — see the affected versions and patch details below.
AWS SDK for PHP has CloudFront Policy Document Injection via Special Characters
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
Summary
This notification is related to the CloudFront signing utilities in the AWS SDK for PHP, which are used to generate Amazon CloudFront signed URLs and signed cookies. A defense-in-depth enhancement has been implemented to improve handling of special characters, such as double quotes and backslashes, in input values.
Impact
The CloudFront signing utilities build policy documents that define access restrictions for signed URLs and cookies. If an application passes unsanitized input containing special characters to these utilities, the resulting policy document may not reflect the application's intended access restrictions. While the SDK was functioning safely within the requirements of the shared responsibility model, additional safeguards have been added to support secure customer implementations. Applications that already follow AWS security best practices for input validation are not impacted.
Impacted versions: 3.11.7 - 3.371.3
Patches
On 3/3/2026, an enhancement was made to the AWS SDK for PHP version 3.371.4. The enhancement ensures that special characters in input values are correctly handled. It is recommended to upgrade to the latest version.
Workarounds
No workarounds are needed, but customers should ensure that the application is following security best practices:
- Implement proper input validation in application code before passing values to CloudFront signing utilities
- Update to the latest AWS SDK release on a regular basis
- Follow AWS security best practices for SDK configuration
References
For any questions or comments about this advisory, it is recommended to contact AWS Security via the vulnerability reporting page or directly via email to [email protected]. Please do not create a public GitHub issue.
Acknowledgement
The Amazon Inspector Security Research team is thanked for identifying this issue and working through the coordinated process.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | aws/aws-sdk-php | ≥ 3.11.7&&< 3.371.4 | 3.371.4composer require aws/aws-sdk-php:^3.371.4 |
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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update aws/aws-sdk-php to 3.371.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-27qh-8cxx-2cr5 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-27qh-8cxx-2cr5 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-27qh-8cxx-2cr5. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-27qh-8cxx-2cr5 in your dependencies?
O3 Security finds GHSA-27qh-8cxx-2cr5 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.