CVE-2026-9704
📛 CVE Title
Keycloak: keycloak: privilege escalation due to oversized subject_token jwt
Description
A flaw was found in Keycloak. An authenticated user with low privileges can exploit this vulnerability by sending an oversized subject_token JSON Web Token (JWT) to the TokenEndpoint. When the token exceeds a 4000-character limit, it is silently dropped, causing the system to fall back to client credentials. This allows the user to gain the permissions of the client's service account, leading to privilege escalation.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- redhat
- CVSS severity
- MEDIUM
- CVSS score
- 6.8 / 10
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N- Effective score
- 6.8 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-1284 - Reserved
- 2026-05-27
- Published
- 2026-05-27 12:56 UTC
- Last updated
- 2026-05-27 15:29 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/9xxx/CVE-2026-9704.json
- Linked Threat
- CVE-2026-9704 — CVE-2026-9704
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-27 14:17:40 UTC
- NVD last modified
- 2026-06-26 08:16:26 UTC
- NVD CVSS v3.1
- 6.8 / 10 MEDIUM source: secalert@redhat.com
- NVD CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N- Exploitability subscore
- 1.6 / 10
- Impact subscore
- 5.2 / 10
- EPSS score
- 0.0032 (probability of exploitation in next 30 days)
- EPSS percentile
- 24.50% vs all CVEs — higher = more likely to be exploited, as of 2026-08-01
NVD / KEV / EPSS data refreshed 2026-08-01 17:05 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-32300 - Assigner
- redhat
- Published
- May 27, 2026, 12:56:00 PM
- Updated
- Jun 26, 2026, 6:46:25 AM
- EUVD base score (CVSS 3.1)
-
6.8 / 10
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N - EUVD-reported EPSS
- 0.3200
- Vendors
- Red Hat
- Products
-
Red Hat build of Keycloak 26.6 (patch: 26.6.3-3)Red Hat build of Keycloak 26.6 (patch: 26.6-6)Red Hat build of Keycloak 26.4 (patch: 26.4.13-1)Red Hat build of Keycloak 26.4 (patch: 26.4-19)
- Aliases
-
GHSA-rr5q-3xwr-f323
ENISA description: A flaw was found in Keycloak. An authenticated user with low privileges can exploit this vulnerability by sending an oversized subject_token JSON Web Token (JWT) to the TokenEndpoint. When the token exceeds a 4000-character limit, it is silently dropped, causing the system to fall back to client credentials. This allows the user to gain the permissions of the client's service account, leading to privilege escalation.
EUVD references (6)
- https://access.redhat.com/errata/RHSA-2026:25097
- https://access.redhat.com/errata/RHSA-2026:25098
- https://access.redhat.com/errata/RHSA-2026:30049
- https://access.redhat.com/errata/RHSA-2026:30050
- https://access.redhat.com/security/cve/CVE-2026-9704
- https://bugzilla.redhat.com/show_bug.cgi?id=2481877
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Red Hat | Red Hat Build of Keycloak | — | — |
Affected products — CPE 2.3 (1) NVD
NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.
cpe:2.3:a:redhat:build_of_keycloak:-:*:*:*:-:*:*:*
Vendor references (2)
References embedded in the original CVE record by the assigning CNA.
- https://access.redhat.com/security/cve/CVE-2026-9704 vdb-entryx_refsource_REDHAT
- RHBZ#2481877 issue-trackingx_refsource_REDHAT
Web references (5)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://access.redhat.com/security/cve/CVE-2026-9704 tenable:access.redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2481877 tenable:bugzilla.redhat.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-9704 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-9704 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (6)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://access.redhat.com/security/cve/CVE-2026-9704 secalert@redhat.com MitigationVendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2481877 secalert@redhat.com Issue TrackingVendor Advisory
- https://access.redhat.com/errata/RHSA-2026:25097 secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:25098 secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:30049 secalert@redhat.com
- https://access.redhat.com/errata/RHSA-2026:30050 secalert@redhat.com
Remediations (19)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:cvetodo.com
How do I fix CVE-2026-9704 ? To remediate CVE-2026-9704 : Check Red Hat's security advisories for official patches and updates. Update Red Hat Build of Keycloak to the latest patched version. Review the references section below for vendor advisories and mitigation guidance. What is the CVSS score of CVE-2026-9704 ?
2026-06-04 00:03 UTC -
web:cyberpress.org
Microsoft's January 2026 Patch Tuesday release delivers fixes for 114 security vulnerabilities across its product ecosystem, including three zero-day flaws that require immediate attention from enterprise security teams. The substantial update addresses critical remote code execution vulnerabilities in core Windows services and Office applications, with particular emphasis on privilege ...
2026-06-04 00:03 UTC -
web:cybersecuritynews.com
Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.
2026-06-04 00:03 UTC -
web:nvd.nist.gov
An official website of the United States government Here's how you know
2026-06-04 00:03 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-06-04 00:03 UTC -
web:redmondmag.com
Microsoft April 2026 Patch Tuesday fixed 163 CVEs , marking its second-largest security update. Three zero-day vulnerabilities impacted SharePoint, Chromium-based Edge workflows and Microsoft Defender.
2026-06-04 00:03 UTC -
web:www.cisa.gov
. For more information see MAR-251132.c1.v1 Exploitation of SharePoint Vulnerabilities and CISA Releases Malware Analysis Report Associated with Microsoft SharePoint Vulnerabilities. Update (07/31/2025): CISA has updated this alert to provide clarification on antivirus and endpoint detection and response (EDR) solutions, and details regarding mitigations related to the IIS server. Update (07 ...
2026-06-04 00:03 UTC -
web:www.helpnetsecurity.com
Microsoft has marked May 2026 Patch Tuesday by releasing fixes for 120+ CVE -numbered vulnerabilities, none of which are actively exploited.
2026-06-04 00:03 UTC -
web:www.notebookcheck.net
Microsoft April 2026 Patch Tuesday fixes 167 vulnerabilities, including an actively exploited SharePoint zero-day. Windows 11 KB5083769 and KB5082052 bring new builds and RDP security.
2026-06-04 00:03 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's June 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-06-04 00:03 UTC -
web:blog.qualys.com
May 2026's Patch Tuesday arrives with Microsoft addressing a fresh set of vulnerabilities across its ecosystem, reinforcing the ongoing need for timely patching in an increasingly threat-heavy…
2026-06-19 02:28 UTC -
web:github.com
Mitigation is available either through a microcode update that fixes the bug, or through a kernel workaround that sets the FP_BACKUP_FIX bit (bit 9) in the DE_CFG MSR, disabling the faulty optimization. Either approach alone is sufficient. Performance impact is negligible. CVE -2023-23583 — Redundant Prefix Issue (Reptar)
2026-06-19 02:28 UTC -
web:securityboulevard.com
Cybersecurity vulnerabilities pose significant risks to organizations in today's digital landscape. Left unaddressed, these vulnerabilities can lead to data breaches, financial losses, and reputational damage. Organizations must decide how to tackle vulnerabilities—through remediation , mitigation , or a combination of both. But which strategy is more effective? This blog explores the ...
2026-06-19 02:28 UTC -
web:www.cisa.gov
If vulnerabilities cannot be remediated within the recommended timeframes, develop a remediation plan for action and coordination across the organization. The remediation plan should include: Vulnerability remediation constraints Interim mitigation actions to overcome constraints Final actions required to remediate vulnerability
2026-06-19 02:28 UTC -
web:www.hipaajournal.com
CISA has released a new risk-based vulnerability remediation framework to help vendors assess vulnerabilities and prioritize patching effectively, concentrating their efforts on mitigating vulnerabilities in the most at-risk assets and addressing vulnerabilities that carry the greatest risk of exploitation.
2026-06-19 02:28 UTC -
web:www.nist.gov
A revision to NIST's catalog of security and privacy safeguards aims to help organizations better manage risks related to software updates and patches. The catalog revision is part of NIST's response to a recent executive order on strengthening the nation's cybersecurity. Completed with the help of a real-time commenting system, the revision is available in several different formats ...
2026-06-19 02:28 UTC -
web:www.rapid7.com
Microsoft is publishing 200 vulnerabilities on June 2026 Patch Tuesday, including an HTTP/2 denial of service vulnerability and an elevation of privilege vulnerability in PowerToys.
2026-06-19 02:28 UTC -
web:www.secure.com
Remediation fully removes a vulnerability by fixing its root cause — through a patch , code fix , or system replacement. Mitigation reduces the risk of exploitation without removing the flaw itself, using controls like network segmentation or access restrictions.
2026-06-19 02:28 UTC -
web:www.upguard.com
Mitigation uses compensating controls, such as WAF rules, to reduce the likelihood of exploitation until a fix is viable, while patching is a specific remediation technique that involves applying vendor-supplied code updates.
2026-06-19 02:28 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-9704.json.
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