CVE-2020-5403: Reactor netty http Improper Handling Of Exceptional Conditions Vulnerability

HIGH
Advisory Identifier: GHSA-hp5x-rqf7-43vf
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CVSS 7.5
CWE-755 CWE-20
Published
Advisory Summary

CVE-2020-5403 is a HIGH (CVSS 7.5) improper handling of exceptional conditions vulnerability (CWE-755: Improper Handling of Exceptional Conditions) affecting Reactor netty http libraries in the Maven ecosystem. The issue involves improper handling of exceptional conditions and improper input validation in reactor netty. Remediation is available by upgrading affected packages to version 0.9.5.

CVE-2020-5403 at a Glance

CVE Identifier CVE-2020-5403
GHSA Identifier GHSA-hp5x-rqf7-43vf
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-755: Improper Handling of Exceptional Conditions
Affected Product Reactor netty http
Package Ecosystem Maven
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-2020-5403

To remediate this vulnerability, upgrade all affected Reactor netty http dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

io.projectreactor.netty:reactor-netty-http fixed: 0.9.5 
<dependency>
    <groupId>io.projectreactor.netty</groupId>
    <artifactId>reactor-netty-http</artifactId>
    <version>0.9.5</version>
</dependency>
Verify Direct and Transitive Dependencies

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

mvn dependency:tree -Dincludes=io.projectreactor.netty

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2020-5403, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=io.projectreactor.netty

Analyze the terminal output to locate any version of Reactor netty http in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.9.5), your application is affected.

Note: The mvn dependency:tree -Dincludes=io.projectreactor.netty command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-755: Improper Handling of Exceptional Conditions, where the product does not handle or incorrectly handles an exceptional condition. In Reactor netty http, 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

Reactor Netty HttpServer, versions 0.9.3 and 0.9.4, is exposed to a URISyntaxException that causes the connection to be closed prematurely instead of producing a 400 response.

CVE-2020-5403 Affected Reactor netty http Versions

1 component(s)
Fixed Versions:
0.9.5
Product / Package Ecosystem Affected Versions Fixed Version
io.projectreactor.netty:reactor-netty-http
maven/io.projectreactor.netty/reactor-netty-http
Maven
≥ 0.9.3
< 0.9.5
0.9.5

References

NVD — CVE-2020-5403 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-5403
Reactor netty http Security Information SECURITY
https://pivotal.io/security/cve-2020-5403

Frequently Asked Questions

What is CVE-2020-5403?
CVE-2020-5403 is a security vulnerability in Reactor netty http involving Improper Handling of Exceptional Conditions and Improper Input Validation in Reactor Netty under CWE-755: Improper Handling of Exceptional Conditions.
Which Reactor netty http versions are affected?
Affected versions include releases prior to 0.9.5 across affected packages: io.projectreactor.netty:reactor-netty-http.
What version fixes CVE-2020-5403?
Upgrading to 0.9.5 (or the latest patched release for your respective branch) resolves the vulnerability.
Is reactor-netty-http affected?
Yes, io.projectreactor.netty:reactor-netty-http is affected in releases prior to 0.9.5. Upgrade your dependency to 0.9.5 or later.
What is the CVSS score of CVE-2020-5403?
CVE-2020-5403 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-2020-5403?
CVE-2020-5403 is classified under CWE-755: Improper Handling of Exceptional Conditions (The product does not handle or incorrectly handles an exceptional condition.).
How can I check Maven dependencies for CVE-2020-5403?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=io.projectreactor.netty'. 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
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-hp5x-rqf7-43vf",
  "modified" : "2022-09-21T19:22:58Z",
  "published" : "2022-02-10T20:24:21Z",
  "aliases" : [ "CVE-2020-5403" ],
  "summary" : "Improper Handling of Exceptional Conditions and Improper Input Validation in Reactor Netty",
  "details" : "Reactor Netty HttpServer, versions 0.9.3 and 0.9.4, is exposed to a URISyntaxException that causes the connection to be closed prematurely instead of producing a 400 response.",
  "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" : "Maven",
      "name" : "io.projectreactor.netty:reactor-netty-http"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.9.3"
      }, {
        "fixed" : "0.9.5"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 0.9.4"
    }
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-5403"
  }, {
    "type" : "WEB",
    "url" : "https://pivotal.io/security/cve-2020-5403"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20", "CWE-755" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-04-22T20:27:06Z",
    "nvd_published_at" : "2020-03-03T19:15:00Z"
  }
}