CVE-2024-21631: vapor Input Validation Flaw — Fix

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.

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CVSS v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Weakness Type (CWE)

CWE-20 Improper Input Validation

CWE-190 Integer Overflow

CWE-1104 CWE-1104

Affected Products

Vendor	Product	Versions
vapor	vapor	< 4.90.0

References

Advisories & Patches

https://github.com/vapor/vapor/commit/6db3d917b5ce5024a84eb265ef65691383305d70 https://github.com/vapor/vapor/security/advisories/GHSA-r6r4-5pr8-gjcp https://github.com/vapor/vapor/commit/6db3d917b5ce5024a84eb265ef65691383305d70 https://github.com/vapor/vapor/security/advisories/GHSA-r6r4-5pr8-gjcp

Frequently Asked Questions

What is CVE-2024-21631? +

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. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2024-21631? +

CVE-2024-21631 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-21631? +

CVE-2024-21631 affects products from vapor, specifically: vapor. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-21631? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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