Prior to version v1.20230419.0, the FormData API implementation was subject to an integer overflow. If a FormData instance contained more than 2^31 elements, the forEach() method could end up reading from the wrong location in memory while iterating over elements. This would most likely lead to a segmentation fault, but could theoretically allow arbitrary undefined behavior. In order for the bug to be exploitable, the process would need to be able to allocate 160GB of RAM. Due to this, the bug was never exploitable on the Cloudflare Workers platform, but could theoretically be exploitable on deployments of workerd running on machines with a huge amount of memory. Moreover, in order to be remotely exploited, an attacker would have to upload a single form-encoded HTTP request of at least tens of gigabytes in size. The application code would then have to use request.formData() to parse the request and formData.forEach() to iterate over this data. Due to these limitations, the exploitation likelihood was considered Low. A fix that addresses this vulnerability has been released in version v1.20230419.0 and users are encouraged to update to the latest version available.
This vulnerability carries a MEDIUM severity rating with a CVSS v3.1 score of 6.5, indicating it can be exploited remotely over the network but requires specific conditions to be met without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts limited data confidentiality, and availability (service disruption) for affected systems. Impacting 1 product from cloudflare organizations running these solutions should prioritize assessment and patching.
Reported in 2023, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.
2023-05-12T11:15:13.033
2024-11-21T07:58:44.983
Modified
CVSSv3.1: 6.5 (MEDIUM)
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Application | cloudflare | workerd | < 1.20230419.0 | Yes |
SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For cloudflare's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.