---
id: CVE-2020-27846
aliases:
  - GHSA-4hq8-gmxx-h6w9
  - BIT-grafana-2020-27846
  - GO-2021-0058
title: XML Processing error in github.com/crewjam/saml
summary: XML Processing error in github.com/crewjam/saml
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
vendor: crewjam
product: github.com/crewjam/saml
ecosystem: go
affected:
  - github.com/crewjam/saml < 0.4.3
patched:
  - github.com/crewjam/saml 0.4.3
published: '2021-06-23'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T03:49:15.079722633Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-4hq8-gmxx-h6w9'
references:
  - url: 'https://github.com/crewjam/saml/security/advisories/GHSA-4hq8-gmxx-h6w9'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2020-27846'
  - url: >-
      https://github.com/crewjam/saml/commit/da4f1a0612c0a8dd0452cf8b3c7a6518f6b4d053
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=1907670'
  - url: 'https://github.com/crewjam/saml'
  - url: >-
      https://grafana.com/blog/2020/12/17/grafana-6.7.5-7.2.3-and-7.3.6-released-with-important-security-fix-for-grafana-enterprise
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3YUTKIRWT6TWU7DS6GF3EOANVQBFQZYI
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ICP3YRY2VUCNCF2VFUSK77ZMRIC77FEM
  - url: 'https://mattermost.com/blog/coordinated-disclosure-go-xml-vulnerabilities'
  - url: 'https://pkg.go.dev/vuln/GO-2021-0058'
  - url: 'https://security.netapp.com/advisory/ntap-20210205-0002'
tags:
  - osv
  - go
epss: 0.04931
epssPercentile: 0.91804
ingestedAt: '2026-09-12T03:13:01.753Z'
---

## Overview

### Impact

There are three vulnerabilities in the go `encoding/xml` package that can allow an attacker to forge part of a signed XML document. For details on this vulnerability see [xml-roundtrip-validator](https://github.com/mattermost/xml-roundtrip-validator)

### Patches

In version 0.4.3, all XML input is validated prior to being parsed.

## Affected packages

- `github.com/crewjam/saml < 0.4.3`

## Remediation

Upgrade to a patched release:

- `github.com/crewjam/saml 0.4.3`