CVE-2024-21631

Integer overflow in URI leading to potential host spoofing

Description

Vapor is an HTTP web framework for Swift. Prior to version 4.90.0, Vapor's `vapor_urlparser_parse` function uses `uint16_t` indexes when parsing a URI's components, which may cause integer overflows when parsing untrusted inputs. This vulnerability does not affect Vapor directly but could impact applications relying on the URI type for validating user input. The URI type is used in several places in Vapor. A developer may decide to use URI to represent a URL in their application (especially if that URL is then passed to the HTTP Client) and rely on its public properties and methods. However, URI may fail to properly parse a valid (albeit abnormally long) URL, due to string ranges being converted to 16-bit integers. An attacker may use this behavior to trick the application into accepting a URL to an untrusted destination. By padding the port number with zeros, an attacker can cause an integer overflow to occur when the URL authority is parsed and, as a result, spoof the host. Version 4.90.0 contains a patch for this issue. As a workaround, validate user input before parsing as a URI or, if possible, use Foundation's `URL` and `URLComponents` utilities.

Categories

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.56%
Vendor Advisory github.com
Affected: vapor vapor
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2024-21631?
CVE-2024-21631 has been scored as a medium severity vulnerability.
How to fix CVE-2024-21631?
To fix CVE-2024-21631, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2024-21631 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-21631 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2024-21631?
CVE-2024-21631 affects vapor vapor.
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