CVE-2020-1727Network attack vector

Client-side attacks via unvalidated IdP authorization URLs

Published Jun 22, 2020 · Updated Aug 4, 2024

Improper input validation in Keycloak before 9.0.2 allows remote authenticated users to craft malicious IdP authorization deep links. The Admin Console accepts a broad set of characters in identity-provider Authorization URL fields without enforcing a safe URL form. Authenticated access to identity-provider settings is required, and crafted links can expose affected clients to further attacks that Red Hat has not specified.

CVSS severity6.4
Medium
EPSS probability0.80%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Keycloak before 9.0.2 allows remote authenticated users to craft malicious IdP authorization deep links. The Admin Console accepts a broad set of characters in identity-provider Authorization URL fields without enforcing a safe URL form. Authenticated access to identity-provider settings is required, and crafted links can expose affected clients to further attacks that Red Hat has not specified.

The record

CVE
CVE-2020-1727
Published
Jun 22, 2020
Updated
Aug 4, 2024
Vendor
Keycloak
Product
Keycloak
Classifications
CWE-20
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 22, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Versions before 9.0.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Keycloak · Keycloakversion=Versions before 9.0.2

Published CVSS scores

6.4Red Hat, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
5.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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