CVE-2021-3426: Software Security Vulnerability Vulnerability

MODERATE
Advisory Identifier: GHSA-6qp6-q95v-x2qw
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CVSS 5.7
CWE-200 CWE-22
Published
Advisory Summary

CVE-2021-3426 is a MODERATE (CVSS 5.7) security vulnerability vulnerability (CWE-200: Exposure of Sensitive Information to an Unauthorized Actor) affecting Software libraries in the Maven ecosystem. The weakness occurs when the product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.. Remediation is available in the latest vendor maintenance releases.

CVE-2021-3426 at a Glance

CVE Identifier CVE-2021-3426
GHSA Identifier GHSA-6qp6-q95v-x2qw
Severity MODERATE
CVSS v3.1 Base Score 5.7
CWE Classification CWE-200: Exposure of Sensitive Information to an Unauthorized Actor
Affected Product Software
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 5.7

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

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

How to Fix CVE-2021-3426

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

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

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2021-3426, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree

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

Note: The mvn dependency:tree 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-200: Exposure of Sensitive Information to an Unauthorized Actor, where the product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. In Software, 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

There's a flaw in Python 3's pydoc. A local or adjacent attacker who discovers or is able to convince another local or adjacent user to start a pydoc server could access the server and use it to disclose sensitive information belonging to the other user that they would not normally be able to access. The highest risk of this flaw is to data confidentiality. This flaw affects Python versions before 3.8.9, Python versions before 3.9.3 and Python versions before 3.10.0a7.

References

NVD — CVE-2021-3426 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3426
Software Security Information SECURITY
https://www.oracle.com/security-alerts/cpuoct2021.html
Software Security Information SECURITY
https://www.oracle.com/security-alerts/cpujan2022.html
Software Security Information SECURITY
https://security.netapp.com/advisory/ntap-20210629-0003
Software Security Information SECURITY
https://security.gentoo.org/glsa/202104-04
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VPX7Y5GQDNB4FJTREWONGC4ZSVH7TGHF
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QNGAFMPIYIVJ47FCF2NK2PIX22HUG35B
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/N6VXJZSZ6N64AILJX4CTMACYGQGHHD5C
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/LM5V4VPLBHBEASSAROYPSHXGXGGPHNOE
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DQYPUKLLBOZMKFPO7RD7CENTXHUUEUV7
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BF2K7HEWADHN6P52R3QLIOX27U3DJ4HI
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/25HVHLBGO2KNPXJ3G426QEYSSCECJDU5
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VPX7Y5GQDNB4FJTREWONGC4ZSVH7TGHF
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QNGAFMPIYIVJ47FCF2NK2PIX22HUG35B
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/N6VXJZSZ6N64AILJX4CTMACYGQGHHD5C
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LM5V4VPLBHBEASSAROYPSHXGXGGPHNOE
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DQYPUKLLBOZMKFPO7RD7CENTXHUUEUV7
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BF2K7HEWADHN6P52R3QLIOX27U3DJ4HI
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/25HVHLBGO2KNPXJ3G426QEYSSCECJDU5
lists.debian.org/debian-lts-announce... WEB
https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html
lists.debian.org/debian-lts-announce... WEB
https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
lists.debian.org/debian-lts-announce... WEB
https://lists.debian.org/debian-lts-announce/2021/04/msg00005.html
cert-portal.siemens.com/productcert/html/ss... WEB
https://cert-portal.siemens.com/productcert/html/ssa-398330.html
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=1935913

Frequently Asked Questions

What is CVE-2021-3426?
CVE-2021-3426 is a security vulnerability in Software classified as a security vulnerability vulnerability under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor.
Which Software versions are affected?
Affected versions include releases prior to current release patches.
What version fixes CVE-2021-3426?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
What is the CVSS score of CVE-2021-3426?
CVE-2021-3426 has a CVSS v3.1 base score of 5.7 (MODERATE) with vector string CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2021-3426?
CVE-2021-3426 is classified under CWE-200: Exposure of Sensitive Information to an Unauthorized Actor (The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.).
How can I check Maven dependencies for CVE-2021-3426?
Run the dependency tree command: 'mvn dependency:tree'. 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 
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  "id" : "GHSA-6qp6-q95v-x2qw",
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  "published" : "2022-05-24T19:02:53Z",
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  "severity" : [ {
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