GHSA-748w-hm6r-qc7v
HIGHGHSA-748w-hm6r-qc7v is a high-severity (CVSS 7.7) CWE-639 vulnerability in code16/sharp. O3 Security confirms whether GHSA-748w-hm6r-qc7v is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Authenticated Sharp users can download unrelated Laravel Storage objects through the generic download endpoint
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-748w-hm6r-qc7v.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-748w-hm6r-qc7v plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 0 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
code16/sharpReal-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
Sharp exposes a generic download endpoint that authorizes access only to the supplied Sharp entity instance, but then reads the target storage disk and path from request parameters.
Because the requested storage object is not bound to the authorized entity instance, an authenticated Sharp user who can view one valid record may use that record as an authorization anchor to download unrelated disk-relative objects from configured Laravel Storage disks.
The confirmed impact is authenticated disclosure of unrelated objects from configured Laravel Storage disks. This issue does not imply arbitrary host filesystem access outside configured Laravel Storage disk roots.
Impact
An authenticated Sharp user with view access to at least one valid Sharp entity instance may be able to download unrelated files from configured Laravel Storage disks by supplying a different disk and path to the generic download endpoint.
Depending on the application, exposed files may include exports, backups, invoices, internal documents, uploads belonging to other records, tenant-specific data, or operational files stored on private application disks.
The attacker does not need authorization to the storage object being downloaded. They only need an authenticated Sharp session and view access to one valid entity instance that can be used as the authorization anchor.
Attack requirements
An attacker must have:
- an authenticated Sharp session
- view access to at least one valid Sharp entity instance
The attacker does not need authorization to the storage object being downloaded.
Affected endpoint
GET /sharp/{globalFilter}/download/{entityKey}/{instanceId?}
Patches
After the fix, requests to the generic download endpoint without a valid signature are rejected. Modifying the disk, path, entityKey, or instanceId parameters of a Sharp-generated download URL invalidates the signature and prevents the modified request from being used to download another storage object.
Workarounds
If upgrading is not immediately possible, applications should restrict downloads.allowed_disks to the smallest possible set of disks required by Sharp downloads.
Applications should also avoid storing sensitive unrelated files on disks reachable by Sharp’s generic download endpoint, and should add application-level controls to ensure that requested files are bound to the authorized record.
Disk allowlisting reduces the reachable storage surface, but it does not fully fix the missing per-record file binding. Upgrading to a patched version is recommended.
Resources
- Laravel signed URLs documentation: https://laravel.com/docs/urls#signed-urls
- CWE-639: https://cwe.mitre.org/data/definitions/639.html
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | code16/sharp | all versions | 9.22.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for code16/sharp. 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 code16/sharp to 9.22.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-748w-hm6r-qc7v 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 GHSA-748w-hm6r-qc7v 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 GHSA-748w-hm6r-qc7v. 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-748w-hm6r-qc7v in your dependencies?
O3 detects GHSA-748w-hm6r-qc7v across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.