Is CVE-2026-18963 actively exploited?

Yes. Previdian has observed exploitation attempts targeting this CVE. Confidence is confirmed.

What exploitation activity has Previdian observed?

Previdian sensors have observed 32 exploitation attempts, 1 unique attacker IP, and 1 country targeting CVE-2026-18963. First observed Aug 25, 2026.

Which versions are affected?

CVE-2026-18963 affects Red Hat Red Hat build of Keycloak 26.4 and 5 other products. Previdian lists 13 version rows; examples include 26.4.15-1 to < * and 26.4-23 to < *.

How should organizations remediate it?

Prioritize immediate patching and validate internet-facing exposure. Monitor for matching exploitation attempts in your environment.

No. CVE-2026-18963 is not currently listed in CISA KEV.

CVE-2026-18963 Exploitation Observed — Red Hat build of Keycloak 26.4, Red Hat build of Keycloak 26.4.15, Red Hat build of Keycloak 26.6, Red Hat build of Keycloak 26.6.6, Red Hat JBoss Enterprise Application Platform Expansion Pack, Red Hat Single Sign-On 7

Q: How should organizations remediate it?

Prioritize immediate patching and validate internet-facing exposure. Monitor for matching exploitation attempts in your environment.

Q: Is it in CISA KEV?

No. CVE-2026-18963 is not currently listed in CISA KEV.

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2026-18963 is an unauthenticated vulnerability affecting Red Hat Red Hat build of Keycloak 26.4 and 5 other products. A flaw was found in the reset-credentials flow of the keycloak-services component, which is the...

Is it exploited?

Yes. Previdian sensors observed exploitation attempts with confirmed confidence.

Who is affected?

Red Hat / Red Hat build of Keycloak 26.4 affected before *.

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

Red Hat build of Keycloak 26.4

A flaw was found in the reset-credentials flow of the keycloak-services component, which is the core engine for identity and access management in Red Hat Build of Keycloak. The issue allows an unauthenticated attacker to force the password reset process for any user without needing to click the required email verification link.

This can result in the attacker gaining full control over target user accounts by directly setting new credentials.

Vendor Product Affected Status

Red Hat Red Hat build of Keycloak 26.4 rhbk/keycloak-operator-bundle Before * Unaffected

Red Hat Red Hat build of Keycloak 26.4 rhbk/keycloak-rhel9 Before * Unaffected

Red Hat Red Hat build of Keycloak 26.4 rhbk/keycloak-rhel9-operator Before * Unaffected

Red Hat Red Hat build of Keycloak 26.4.15 keycloak-services All versions (default: unaffected) Unaffected

Red Hat Red Hat build of Keycloak 26.4.15 rhbk-openshift-rhel9/rhbk-openshift-rhel9 All versions (default: unaffected) Unaffected

Red Hat Red Hat build of Keycloak 26.6 rhbk/keycloak-operator-bundle Before * Unaffected

Red Hat Red Hat build of Keycloak 26.6 rhbk/keycloak-rhel9 Before * Unaffected

Red Hat Red Hat build of Keycloak 26.6 rhbk/keycloak-rhel9-operator Before * Unaffected

Red Hat Red Hat build of Keycloak 26.6.6 keycloak-services All versions (default: unaffected) Unaffected

Red Hat Red Hat build of Keycloak 26.6.6 rhbk-keycloak-rhel9/rhbk-keycloak-rhel9 All versions (default: unaffected) Unaffected

Red Hat Red Hat build of Keycloak 26.6.6 rhbk-openshift-rhel9/rhbk-openshift-rhel9 All versions (default: unaffected) Unaffected

Red Hat Red Hat JBoss Enterprise Application Platform Expansion Pack keycloak-services All versions (default: unaffected) Unaffected

Red Hat Red Hat Single Sign-On 7 keycloak-services All versions (default: unaffected) Unaffected

View vendor advisory

Published: 18 Aug 2026
Exploitation Reported: 25 Aug 2026
Attack vector: Remote
Complexity: Low
Privileges: None
User interaction: None

CVE References

CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2026-18963
RHSA-2026:56519 access.redhat.com · Vendor Advisory https://access.redhat.com/errata/RHSA-2026:56519
RHSA-2026:56520 access.redhat.com · Vendor Advisory https://access.redhat.com/errata/RHSA-2026:56520
RHSA-2026:56523 access.redhat.com · Vendor Advisory https://access.redhat.com/errata/RHSA-2026:56523
RHSA-2026:56524 access.redhat.com · Vendor Advisory https://access.redhat.com/errata/RHSA-2026:56524
RHBZ#2511595 bugzilla.redhat.com · Issue Tracking https://bugzilla.redhat.com/show_bug.cgi?id=2511595
VDB Entry — access.redhat.com access.redhat.com · VDB Entry https://access.redhat.com/security/cve/CVE-2026-18963

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

Previdian

Recorded 25 Aug 2026

Independent exploitation attestation added to the Previdian record.

Active exploitation observed

Previdian sensor

First observed 25 Aug 2026

First-party sensor telemetry confirms matching exploitation attempts.

Proof of concept available

GitHub

Recorded 20 Aug 2026

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access

Source	Added
Previdian First	2026-08-25 15:13 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

First-party evidence of exploitation activity

Aggregate observations show the scale, recency, and distribution of activity without overstating sparse data.

32

Attempts observed

1

Unique attacker IPs

1

Attacker countries

US

1

Sensors observed

Exploitation attempts over the last 7 days

Daily events observed by Previdian sensors

Updated 26 Aug 2026

0

32

0

20 Aug 21 Aug 22 Aug 23 Aug 24 Aug 25 Aug 26 Aug

First observed 25 Aug 2026 · Last observed 25 Aug 2026

Pro adds sensor region and window summaries. Enterprise adds raw IPs, paths, User-Agents, and payloads.

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Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets: 32
User-Agents: 1

Raw values available in Pro and Enterprise.

Scanner coverage

Nuclei template detected 25 Aug 2026.

View Nuclei template

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

Learn about Pro API access

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner	Reference	Detected
Nuclei	https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-18963.yaml	25 Aug 2026

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

9.1 Critical

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

EPSS

2.8%

Weaknesses

Weak Password Recovery Mechanism for Forgotten Password CWE-640

Recent mention · TheHackerNews

Critical Keycloak Password Reset Flaw Could Let Unauthenticated Attackers Take Over Any Account

Red Hat and the Keycloak project have released patches to address a critical security flaw in the open-source identity and access management server that could allow an unauthenticated remote attacker to take over any user account by forcing a password reset. The...

Read full advisory

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

gman0x00/keycloak-CVE-2026-18963

github · Created 2026-08-25 15:05:11 UTC · 0 stars · AI assessment 90%

PoC, Dockerfile playground and root cause from patch diff analysis.

prot0tw/Keycloak_CVE-2026-18963_PoC

github · Created 2026-08-25 02:28:04 UTC · 7 stars · AI assessment 90%

This repo is poc of cve-2026-18963. Please use it on legal products (lab, local,...).

prot0tw/CVE-2026-18963

github · Created 2026-08-25 02:28:04 UTC · 0 stars · AI assessment 90%

Red-Darkin/CVE-2026-18963-keycloak

github · Created 2026-08-24 23:40:17 UTC · 2 stars · AI assessment 90%

T0w0T/POC-CVE-2026-18963

github · Created 2026-08-24 13:00:27 UTC · 0 stars · AI assessment 90%

Keycloak reset-credentials flow: unauthenticated account takeover (CWE-640)

pruva · Created 2026-08-24 11:14:39 UTC

Severity: CRITICAL | CVE: CVE-2026-18963 | Package: org.keycloak:keycloak-services (Maven)

minh3102011/CVE-2026-18963_analyst

github · Created 2026-08-24 08:49:49 UTC · 0 stars · AI assessment 85%

Snizi/CVE-2026-18963-Exploit

github · Created 2026-08-20 22:01:11 UTC · 0 stars · AI assessment 90%

Exploit for KeyCloak CVE-2026-18963

Keycloak < 26.7.2 - Unauthenticated Account Takeover via Reset-Credentials Bypass

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

25 Aug 2026
Observed by Previdian sensors

Evidence-backed exploitation signal
25 Aug 2026
Indicator of compromise added

Indicators of compromise recorded
25 Aug 2026
Nuclei template available

Scanner coverage available
20 Aug 2026
Public PoC available

Public proof-of-concept code published
18 Aug 2026
Added to the Previdian watchlist

Added to the Previdian curated list for closer monitoring
18 Aug 2026
CVE published

Vulnerability disclosed publicly
05 Aug 2026
CVE ID reserved

Identifier reserved by the CNA

Pro API

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Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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Evidence confidence and provenance
First-party sensor telemetry
PoC and scanner references
Affected versions and enrichment
Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2026-18963

Free JSON includes basic KEV fields

{
  "cve_id": "CVE-2026-18963",
  "confidence": "Confirmed",
  "cvss_score": 9.1,
  "cvss_estimated": false,
  "epss_score": 0.02788,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 32, "sensors": 1 }
}

CVE-2026-18963