CVE-2023-6787: keycloak Auth Bypass — Fix

Description

A flaw was found in Keycloak that occurs from an error in the re-authentication mechanism within org.keycloak.authentication. This flaw allows hijacking an active Keycloak session by triggering a new authentication process with the query parameter "prompt=login," prompting the user to re-enter their credentials. If the user cancels this re-authentication by selecting "Restart login," an account takeover may occur, as the new session, with a different SUB, will possess the same SID as the previous session.

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CVSS v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Weakness Type (CWE)

CWE-287 Improper Authentication

Affected Products

Vendor	Product	Versions
redhat	build_of_keycloak	All
redhat	keycloak	< 22.0.10
redhat	keycloak	23.0.0 — 24.0.3

References

Advisories & Patches

https://access.redhat.com/errata/RHSA-2024:1867 https://access.redhat.com/errata/RHSA-2024:1868 https://access.redhat.com/security/cve/CVE-2023-6787 https://bugzilla.redhat.com/show_bug.cgi?id=2254375 https://github.com/keycloak/keycloak/security/advisories/GHSA-c9h6-v78w-52wj https://access.redhat.com/errata/RHSA-2024:1867 https://access.redhat.com/errata/RHSA-2024:1868 https://access.redhat.com/security/cve/CVE-2023-6787 https://bugzilla.redhat.com/show_bug.cgi?id=2254375

Frequently Asked Questions

What is CVE-2023-6787? +

A flaw was found in Keycloak that occurs from an error in the re-authentication mechanism within org.keycloak.authentication. This flaw allows hijacking an active Keycloak session by triggering a new authentication process with the query parameter "prompt=login," prompting the user to re-enter their credentials. If the user cancels this re-authentication by selecting "Restart login," an account takeover may occur, as the new session, with a different SUB, will possess the same SID as the previous session. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2023-6787? +

CVE-2023-6787 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-6787? +

CVE-2023-6787 affects products from redhat, specifically: build_of_keycloak, keycloak. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-6787? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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