Cloudflare workerd prior 1.20230419.0 forEach buffer under-read

Summaryinfo

A vulnerability described as problematic has been identified in Cloudflare workerd. Affected is the function forEach. Executing a manipulation can lead to buffer under-read. This vulnerability appears as CVE-2023-2512. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic was found in Cloudflare workerd (Cloud Software). This vulnerability affects the function forEach. The manipulation with an unknown input leads to a buffer under-read vulnerability. The CWE definition for the vulnerability is CWE-127. The product reads from a buffer using buffer access mechanisms such as indexes or pointers that reference memory locations prior to the targeted buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The weakness was presented 05/12/2023 as GHSA-8vx6-69vg-c46f. The advisory is available at github.com. This vulnerability was named CVE-2023-2512 since 05/04/2023. Technical details are known, but there is no available exploit.

Upgrading to version 1.20230419.0 eliminates this vulnerability. The upgrade is hosted for download at github.com.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Cloud Software

Vendor

• Cloudflare

Name

• workerd

Website

• Product: https://github.com/cloudflare/workerd/

CPE 2.3info

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CPE 2.2info

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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