CVE-2020-29511
Description
A flaw was found in go. Encoding and decoding of XML elements could lead to changes in the observed integrity. An attacker could use this flaw to trick applications which rely on element integrity for security decisions to make those decisions incorrectly. Known vulnerability use-cases are SAML and XML-DSig.
Statement
All uses of xml/encoding package in OpenShift Container Platform, OpenShift Jaeger, OpenShift Service Mesh (OSSM), OpenShift Virtualization and OpenShift Container Storage do not rely on XML stability. We have assigned CVE-2020-27846 for crewjam/saml, and CVE-2020-27847 for dexidp/dex Go modules which are known to use encoding/xml in an unsafe way.
As it is unlikely for there to be any fix for this issue in Go's encoding/xml library, and the library should not be relied upon for security-sensitive protocols such as SAML and XML-DSig, there is currently no plan to fix this in golang as shipped in Red Hat Enterprise Linux 7, 8, or Red Hat Developer Tools.
Mitigation
While there is unlikely to be any fix for this issue Go's encoding/xml library affected users can workaround the vulnerability by using Mattermost's xml-roundtrip-validator [1].
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.6 | 5.6 | N/A |
| Attack Vector | Network | Network | N/A |
| Attack Complexity | High | High | N/A |
| Privileges Required | None | None | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | Low | Low | N/A |
| Integrity Impact | Low | Low | N/A |
| Availability Impact | Low | Low | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
NVD: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
Red Hat CVSS v3 Score Explanation
This issue only affects Go applications which use encoding/xml and rely on the stability of XML structures during round-trips.
Understanding the Weakness (CWE)
Integrity
Technical Impact: Unexpected State
Frequently Asked Questions
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