CVE-2024-21631 Integer overflow in URI leading to potential host spoofing
An integer overflow in Vapor's URI parser allows attackers to spoof hosts, potentially bypassing security checks in applications relying on this library.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-21631?
CVE-2024-21631 is a medium-severity vulnerability in vapor, published on 3 Jan 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Which versions are affected by CVE-2024-21631?
2 open source packages ship an affected version, including github.com/vapor/vapor. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
github.com/vapor/vapor SwiftURL | All versions | 4.90.0 |
github.com/vapor/vapor SwiftURL | All versions | 4.90.0 |
Products include Vapor Vapor.
How do I fix CVE-2024-21631?
Upgrade github.com/vapor/vapor to 4.90.0 or later.
Is CVE-2024-21631 being exploited?
There is no known exploitation of CVE-2024-21631 in the wild and no public exploit code.
Other vulnerabilities in vapor
Sources
Also known as GHSA-r6r4-5pr8-gjcp.