Skip to content
Noroxi
NVD / CVE Program· CNA redhat

CVE-2026-19607: Keycloak-services: keycloak-services: broker-originated username collision causes account lockout

Noroxi assessment

Priority: Monitor (action score 21/100)

  • Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.68% (FIRST EPSS); higher than 52.7% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • According to the record, no fixed version is available yet.

Low priority for now. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A flaw was found in the first-broker-login flow of the keycloak-services component. This component handles the initial authentication and account linking when a user logs in via an external identity provider. The issue allows an attacker to register a matching username on an external provider to trigger a collision in Keycloak, which results in the legitimate user being locked out of their account.

MediumCVSS 5.3 · v3.1—Proof of concept No fix recorded
Published
Sep 16, 2026
Updated
Sep 16, 2026
EPSS
0.6% · 52th percentile

Report tools

JSON

Action score

21

Monitor

Low priority for now.

CVSS
21 / 40 · 5.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.6%

CISA SSVC decision

Exploitation
none
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · redhat
5.3
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • Proof of concept exists, no weaponized module
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-19607

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.

  • Red Hat Red Hat build of Keycloak 26.4

    • 26.4.16-2 and laternot affected · rpm
    • 26.4-26 and laternot affected · rpm
    • 26.4-26 and laternot affected · rpm
  • Red Hat Red Hat build of Keycloak 26.4.16

    • all versionsunknown
    • all versionsunknown
  • Red Hat Red Hat build of Keycloak 26.6

    • 26.6.7-3 and laternot affected · rpm
    • 26.6-20 and laternot affected · rpm
    • 26.6-20 and laternot affected · rpm
  • Red Hat Red Hat build of Keycloak 26.6.7

    • all versionsunknown
    • all versionsunknown
  • Red Hat Red Hat Single Sign-On 7

    • all versionsunknown

Other highest-scoring records for the same primary product.

  • CVE-2026-18963Keycloak-services: keycloak-services: unauthenticated account takeover via reset-credentials flow bypass
    37Monitor
  • CVE-2026-1486Org.keycloak.protocol.oidc.grants: disabled identity providers are still accepted for jwt authorization grant
    35Monitor
  • CVE-2026-74909Keycloak-services: keycloak-services: incomplete fix for cve-2026-15573 allows policy enforcer bypass via percent-encoded uri segments
    32Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-18212Sep 16, 2026 · Keycloak-services: keycloak-services: saml redirect deflate helpers leak native zlib state
    30Monitor
  • ← EarlierCVE-2026-79651Sep 16, 2026 · Keycloak-services: keycloak-services: unauthenticated dos via unbounded locale caching
    30Monitor
  • ← EarlierCVE-2026-17526Sep 16, 2026 · Keycloak-services: keycloak-services: privilege escalation via impersonation role allows takeover of realm administrator accounts
    28Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

  • Proof-of-concept repository on GitHub ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Proof-of-concept repository on GitHubstars:32026-08-08

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. First PoC-40 d
  2. Published
  3. TodayNov 6, 2026+51 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

—

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

  • CVE-2026-749090 days apartKeycloak-services: keycloak-services: incomplete fix for cve-2026-15573 allows policy enforcer bypass via percent-encoded uri segments
    32Monitor
  • CVE-2026-197297 days apartKeycloak-services: keycloak-services: incomplete fix for arbitrary filesystem path probing via keystore parameters
    19Monitor

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
low · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
Low

CVSS vector

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

nvd-secondary

Root cause

Authentication is added route by route instead of being enforced in one place. When a route added later bypasses the shared middleware, the session check never runs for it.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

ts
app.use("/admin", requireSession, adminRouter);
// Route added later skips the middlewareapp.post("/admin-api/config", updateConfig);

Fixed

ts
const admin = express.Router();admin.use(requireSession, requireRole("admin"));
admin.post("/config", updateConfig);app.use("/admin", admin);

Change log

  1. Exploit maturitynone → poc

For records you follow, these changes also arrive as notifications. →

References

All records