CVE-2022-24668: Github.com/apple/swift nio http2 Denial of Service Vulnerability

HIGH
Advisory Identifier: GHSA-pgfx-g6rc-8cjv
CVSS 7.5
CWE-241
Published
Advisory Summary

CVE-2022-24668 is a HIGH (CVSS 7.5) denial of service vulnerability (CWE-241: Improper Handling of Unexpected Data Type) affecting Github.com/apple/swift nio http2 libraries in the SwiftURL ecosystem. The issue involves swift-nio-http2 vulnerable to denial of service via altsvc or origin frames. Remediation is available by upgrading affected packages to version 1.19.2.

CVE-2022-24668 at a Glance

CVE Identifier CVE-2022-24668
GHSA Identifier GHSA-pgfx-g6rc-8cjv
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-241: Improper Handling of Unexpected Data Type
Affected Product Github.com/apple/swift nio http2
Package Ecosystem SwiftURL
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity None (I:N)
Availability High (A:H)

How to Fix CVE-2022-24668

To remediate this vulnerability, upgrade all affected Github.com/apple/swift nio http2 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/apple/swift-nio-http2 fixed: 1.19.2
Upgrade github.com/apple/swift-nio-http2 to 1.19.2
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for github.com/apple/swift-nio-http2

How to Check if You Are Affected

To determine whether your application is affected by CVE-2022-24668, inspect your project dependencies for Github.com/apple/swift nio http2:

inspect dependencies for github.com/apple/swift-nio-http2

Analyze the terminal output to locate any version of Github.com/apple/swift nio http2 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.19.2), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-241: Improper Handling of Unexpected Data Type, where the product does not handle or incorrectly handles when a particular element is not the expected type, e.g. it expects a digit (0-9) but is provided with a letter (a-z). In Github.com/apple/swift nio http2, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

A program using swift-nio-http2 is vulnerable to a denial of service attack caused by a network peer sending ALTSVC or ORIGIN frames. This attack affects all swift-nio-http2 versions from 1.0.0 to 1.19.1. It is fixed in 1.19.2 and later releases. This vulnerability is caused by a logical error after frame parsing but before frame handling. ORIGIN and ALTSVC frames are not currently supported by swift-nio-http2, and should be ignored. However, one code path that encounters them has a deliberate trap instead. This was left behind from the original development process and was never removed. Sending an ALTSVC or ORIGIN frame does not require any special permission, so any HTTP/2 connection peer may send such a frame. For clients, this means any server to which they connect may launch this attack. For servers, anyone they allow to connect to them may launch such an attack. The attack is low-effort: it takes very little resources to send one of these frames. The impact on availability is high: receiving the frame immediately crashes the server, dropping all in-flight connections and causing the service to need to restart. It is straightforward for an attacker to repeatedly send these frames, so attackers require very few resources to achieve a substantial denial of service. The attack does not have any confidentiality or integrity risks in and of itself. This is a controlled, intentional crash. However, sudden process crashes can lead to violations of invariants in services, so it is possible that this attack can be used to trigger an error condition that has confidentiality or integrity risks. The risk can be mitigated if untrusted peers can be prevented from communicating with the service. This mitigation is not available to many services. The issue is fixed by rewriting the parsing code to correctly handle the condition. The issue was found by automated fuzzing by oss-fuzz.

CVE-2022-24668 Affected Github.com/apple/swift nio http2 Versions

1 component(s)
Fixed Versions:
1.19.2
Product / Package Ecosystem Affected Versions Fixed Version
github.com/apple/swift-nio-http2
SwiftURL
≥ 1.0.0
< 1.19.2
1.19.2

References

Frequently Asked Questions

What is CVE-2022-24668?
CVE-2022-24668 is a security vulnerability in Github.com/apple/swift nio http2 involving swift-nio-http2 vulnerable to denial of service via ALTSVC or ORIGIN frames under CWE-241: Improper Handling of Unexpected Data Type.
Which Github.com/apple/swift nio http2 versions are affected?
Affected versions include releases prior to 1.19.2 across affected packages: github.com/apple/swift-nio-http2.
What version fixes CVE-2022-24668?
Upgrading to 1.19.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/apple/swift-nio-http2 affected?
Yes, github.com/apple/swift-nio-http2 is affected in releases prior to 1.19.2. Upgrade your dependency to 1.19.2 or later.
What is the CVSS score of CVE-2022-24668?
CVE-2022-24668 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
What CWE is associated with CVE-2022-24668?
CVE-2022-24668 is classified under CWE-241: Improper Handling of Unexpected Data Type (The product does not handle or incorrectly handles when a particular element is not the expected type, e.g. it expects a digit (0-9) but is provided with a letter (A-Z).).
How can I check SwiftURL dependencies for CVE-2022-24668?
Run the dependency tree command: 'inspect dependencies for github.com/apple/swift-nio-http2'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-pgfx-g6rc-8cjv",
  "modified" : "2023-06-19T16:50:37Z",
  "published" : "2023-05-18T17:32:00Z",
  "aliases" : [ "CVE-2022-24668" ],
  "summary" : "swift-nio-http2 vulnerable to denial of service via ALTSVC or ORIGIN frames",
  "details" : "A program using swift-nio-http2 is vulnerable to a denial of service attack caused by a network peer sending ALTSVC or ORIGIN frames. This attack affects all swift-nio-http2 versions from 1.0.0 to 1.19.1. It is fixed in 1.19.2 and later releases.\n\nThis vulnerability is caused by a logical error after frame parsing but before frame handling. ORIGIN and ALTSVC frames are not currently supported by swift-nio-http2, and should be ignored. However, one code path that encounters them has a deliberate trap instead. This was left behind from the original development process and was never removed.\n\nSending an ALTSVC or ORIGIN frame does not require any special permission, so any HTTP/2 connection peer may send such a frame. For clients, this means any server to which they connect may launch this attack. For servers, anyone they allow to connect to them may launch such an attack.\n\nThe attack is low-effort: it takes very little resources to send one of these frames. The impact on availability is high: receiving the frame immediately crashes the server, dropping all in-flight connections and causing the service to need to restart. It is straightforward for an attacker to repeatedly send these frames, so attackers require very few resources to achieve a substantial denial of service.\n\nThe attack does not have any confidentiality or integrity risks in and of itself. This is a controlled, intentional crash. However, sudden process crashes can lead to violations of invariants in services, so it is possible that this attack can be used to trigger an error condition that has confidentiality or integrity risks.\n\nThe risk can be mitigated if untrusted peers can be prevented from communicating with the service. This mitigation is not available to many services.\n\nThe issue is fixed by rewriting the parsing code to correctly handle the condition. The issue was found by automated fuzzing by oss-fuzz.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "SwiftURL",
      "name" : "github.com/apple/swift-nio-http2"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.0.0"
      }, {
        "fixed" : "1.19.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/apple/swift-nio-http2/security/advisories/GHSA-pgfx-g6rc-8cjv"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2022-24668"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/apple/swift-nio-http2/commit/000ca94f9de92c95b9ac85d44600b7b0fe25a3e5"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/apple/swift-nio-http2"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/apple/swift-nio-http2/releases/tag/1.19.2"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-241" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2023-05-18T17:32:00Z",
    "nvd_published_at" : null
  }
}