CVE-2026-97174

Keycloak-services: keycloak-services: ciba sub parameter injection causes attacker authentication to issue victim tokens

Products / packages Red Hat build of Keycloak 26.6 · Red Hat build of Keycloak 26.6.8 · Red Hat Single Sign-On 7

Published 05/11/2026, 17:15:54 UTC

Severity and exploitation

Not in CISA KEV

KEV coverage does not rule out exploitation.

KEV checked 14/11/2026, 21:00:34 UTC

redhat · CVSS:3.1 · 6.8

Assessment vector

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

Severity

medium6.8

CVSS measures technical severity, not the likelihood of an attack.

Known exploitation

Not listed in the checked CISA KEV catalog

Absence from CISA KEV does not rule out attacks.

Public exploit

Not established by this record

Missing evidence does not mean no public exploit exists.

Remediation

Source guidance available

Review the recorded instructions. Guidance may be a workaround rather than a fixed version.

What this means

A flaw in Keycloak's Client-Initiated Backchannel Authentication (CIBA) implementation allows attackers to authenticate as themselves but receive security tokens belonging to a different victim user. The CIBA endpoint fails to properly validate the sub parameter. The affected product is Red Hat build of Keycloak 26.6, but the exact affected versions are unclear.

Summarized by @cf/meta/llama-3.3-70b-instruct-fp8-fast. Verify details against the original sources.

Attack conditions

No attack-condition excerpt has been identified here. Review the full source description and references for authentication, network access, and configuration requirements.

Review supporting sources →

Affected versions

Check the exact model, release, and any platform requirements against your installation.

Red Hat · redhat

Red Hat build of Keycloak 26.6

1 range

redhat version evidence

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unaffected

26.6.8-2 → before *

rpm versions

Other versions: affected

Product identifiers (CPE)

cpe:/a:redhat:build_keycloak:26.6::el9

Red Hat · redhat

Red Hat build of Keycloak 26.6

1 range

redhat version evidence

Check a product version

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unaffected

26.6-24 → before *

rpm versions

Other versions: affected

Product identifiers (CPE)

cpe:/a:redhat:build_keycloak:26.6::el9

Red Hat · redhat

Red Hat build of Keycloak 26.6

1 range

redhat version evidence

Check a product version

Compare with this publisher’s ranges. This does not inspect your installation.

unaffected

26.6-24 → before *

rpm versions

Other versions: affected

Product identifiers (CPE)

cpe:/a:redhat:build_keycloak:26.6::el9

Red Hat · redhat

Red Hat build of Keycloak 26.6.8

0 ranges

redhat version evidence

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Other versions: unaffected

Product identifiers (CPE)

cpe:/a:redhat:build_keycloak:26.6::el9

Red Hat · redhat

Red Hat build of Keycloak 26.6.8

0 ranges

redhat version evidence

Check a product version

Compare with this publisher’s ranges. This does not inspect your installation.

Other versions: unaffected

Product identifiers (CPE)

cpe:/a:redhat:build_keycloak:26.6::el9

Red Hat · redhat

Red Hat Single Sign-On 7

0 ranges

redhat version evidence

Check a product version

Compare with this publisher’s ranges. This does not inspect your installation.

Other versions: unaffected

Product identifiers (CPE)

cpe:/a:redhat:red_hat_single_sign_on:7

Automatic dependency matching is unavailable for this record. Use the product evidence and publisher’s instructions to check your installation.

What to do

Compare your installed product and version with the affected versions above. A matching product name alone does not confirm exposure.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

redhat guidance ↗

cve.new guidance unless attributed to a publisher. This page does not inspect your installation.

Public exploit evidence

No public exploit reference is identified in the imported evidence. This is not a claim that no exploit exists.

Original source description

Read the full publisher description

A flaw was found in the Client-Initiated Backchannel Authentication (CIBA) implementation of Keycloak. The CIBA endpoint fails to properly validate the sub parameter, allowing it to be stored as an additional request parameter. During the token issuance process, this injected value overwrites the legitimate subject identifier. This allows an attacker to authenticate as themselves but receive security tokens belonging to a different victim user, leading to unauthorized account access.

References

4 sources

access.redhat.com/errata/RHSA-2026:95761

Vendor advisoryredhat

access.redhat.com/errata/RHSA-2026:95762

Vendor advisoryredhat

access.redhat.com/security/cve/CVE-2026-97174

Security advisoryredhat

bugzilla.redhat.com/show_bug.cgi

Source referenceredhat

Inside the record

Evidence available

Package identity · not supplied

Version evidence

Remediation guidance

Weakness classification

Additional publishers

Describes the evidence in this view, not whether the product is safe.

Original records

CVE-2026-97174

View the latest unmodified CVE JSON from the official source. It may be newer than this imported page.

cve.new JSON →

Underlying weaknesses

The source’s classification of what caused the vulnerability.

CWE-20 ↗

Improper Input Validation

redhat

Contributing organizations · 2

redhat

Assigning organization

2026-11-06

CISA-ADP

Additional data publisher

2026-11-05

Timeline

All times UTC

5 Nov 2026, 17:15
Advisory published
Publication date supplied by the source.
6 Nov 2026, 17:12
Source updated
Latest modification date supplied by the source.
6 Nov 2026, 18:03
Last imported by cve.new
Latest catalog import, not the date we first saw this advisory.

What changed

Follow changes

CVE · CVE-2026-971742026-11-06

Observed 2026-11-06T18:03:41.704Z · upstream updated 2026-11-06T17:12:36.994Z

Product or version evidence changed

before

[
  {
    "vendor": "Red Hat",
    "name": "Red Hat build of Keycloak 26.6.8",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:26.6::el9"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat build of Keycloak 26.6.8",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:26.6::el9"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat Single Sign-On 7",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:red_hat_single_sign_on:7"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  }
]

after

[
  {
    "vendor": "Red Hat",
    "name": "Red Hat build of Keycloak 26.6",
    "platforms": [],
    "versions": [
      {
        "version": "26.6.8-2",
        "status": "unaffected",
        "lessThan": "*",
        "versionType": "rpm"
      }
    ],
    "defaultStatus": "affected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:26.6::el9"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat build of Keycloak 26.6",
    "platforms": [],
    "versions": [
      {
        "version": "26.6-24",
        "status": "unaffected",
        "lessThan": "*",
        "versionType": "rpm"
      }
    ],
    "defaultStatus": "affected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:26.6::el9"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat build of Keycloak 26.6",
    "platforms": [],
    "versions": [
      {
        "version": "26.6-24",
        "status": "unaffected",
        "lessThan": "*",
        "versionType": "rpm"
      }
    ],
    "defaultStatus": "affected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:26.6::el9"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat build of Keycloak 26.6.8",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:26.6::el9"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat build of Keycloak 26.6.8",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:26.6::el9"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat Single Sign-On 7",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:red_hat_single_sign_on:7"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  }
]

References changed

before

[
  "https://access.redhat.com/errata/RHSA-2026:95761",
  "https://access.redhat.com/security/cve/CVE-2026-97174",
  "https://bugzilla.redhat.com/show_bug.cgi?id=2539961"
]

after

[
  "https://access.redhat.com/errata/RHSA-2026:95761",
  "https://access.redhat.com/errata/RHSA-2026:95762",
  "https://access.redhat.com/security/cve/CVE-2026-97174",
  "https://bugzilla.redhat.com/show_bug.cgi?id=2539961"
]

CVE · CVE-2026-971742026-11-06

Observed 2026-11-06T10:31:12.219Z · upstream updated 2026-11-06T10:23:55.496Z

Product or version evidence changed

before

[
  {
    "vendor": "Red Hat",
    "name": "Red Hat Build of Keycloak",
    "platforms": [],
    "versions": [],
    "defaultStatus": "affected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat Build of Keycloak",
    "platforms": [],
    "versions": [],
    "defaultStatus": "affected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat Single Sign-On 7",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:red_hat_single_sign_on:7"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  }
]

after

[
  {
    "vendor": "Red Hat",
    "name": "Red Hat build of Keycloak 26.6.8",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:26.6::el9"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat build of Keycloak 26.6.8",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:build_keycloak:26.6::el9"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  },
  {
    "vendor": "Red Hat",
    "name": "Red Hat Single Sign-On 7",
    "platforms": [],
    "versions": [],
    "defaultStatus": "unaffected",
    "cpes": [
      "cpe:/a:redhat:red_hat_single_sign_on:7"
    ],
    "source": "redhat",
    "url": "https://www.cve.org/CVERecord?id=CVE-2026-97174"
  }
]

References changed

before

[
  "https://access.redhat.com/security/cve/CVE-2026-97174",
  "https://bugzilla.redhat.com/show_bug.cgi?id=2539961"
]

after

[
  "https://access.redhat.com/errata/RHSA-2026:95761",
  "https://access.redhat.com/security/cve/CVE-2026-97174",
  "https://bugzilla.redhat.com/show_bug.cgi?id=2539961"
]

Large field values are marked as truncated previews. Original source snapshots remain retained.

Showing up to 50 most recent observed changes.

Reading the signals

Severity · CVSS: Technical impact and attack conditions. The headline is the highest imported catalog score; sources may disagree.
Observed exploitation · KEV: An absent or unavailable KEV listing does not establish that exploitation has not occurred.
Predicted exploitation · EPSS: No EPSS estimate available in this record.

CISA-ADP · SSVC

CISA Coordinator · 2026-11-05

Exploitation: none
Automatable: no
Technical Impact: total

SSVC describes the publisher’s decision context. Your organization’s exposure and priorities may differ.

Record identifiers

Aliases: None recorded

Source evidence

Request a correction or dispute

Start with the assigning organization for this record. Include the CVE ID, the disputed information, and supporting evidence. A dispute does not itself reject a record.

Find the responsible CNA →Official dispute and escalation process ↗

CVE CVE-2026-97174