CVE-2026-16442

CRITICALNVD 9.89.8
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

This critical-severity CVE scores 9.8 under NVD CVSS v3. EPSS exploit probability: 0.3% (24th percentile of EPSS-scored CVEs). GitHub Security Advisory CVSS 7.4 is lower than this score; a lower GitHub score revises it only when its advisory is newer than the CVE record's last change, and this advisory (published 2026-08-05) is not newer than that change (2026-08-31), so it does not.

Triggered by: Headline CVSS from NVD CVSS v3
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3

Also known asEUVD-2026-53395 (ENISA EUVD) · GHSA-vj6m-hv26-qx79 (GitHub Security Advisories)Source: ENISA EUVD

9.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 9.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

A flaw was found in the SAML broker component of Keycloak, which is used to manage identity federation and user authentication. The issue occurs because the IdP-initiated Single Sign-On endpoint fails to check if a provider is restricted to account linking only. This allows an attacker with control over a linked upstream identity to bypass login restrictions and gain full access to a local user account.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
44
EG Risk 44/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.3% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.3%
EPSS %ILE
24th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
EG Likelihood
0.3% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-12). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

August 5, 2026

Last Modified

August 31, 2026

Advisory Details (6)

Auto-updated Oct 31, 2026
Patch available. Sources: redhat.
Red Hat

2503138 – (CVE-2026-16442) CVE-2026-16442 keycloak-services: keycloak-services: SAML IdP-initiated broker login bypasses link-only restriction

https://bugzilla.redhat.com/show_bug.cgi?id=2503138
Red HatMentions a patch (unverified)

CVE-2026-16442 - Red Hat Customer Portal

Affected: Red Hat Enterprise Linux 8 or OpenShift Container Platform 4, is affected by this vulnerability and a fix may be released to a

https://access.redhat.com/security/cve/CVE-2026-16442
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:50849
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:50848
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:50847
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:50846

Patch Availability(3)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatrhbk/keycloak-rhel9-operator:26.6-112026-08-05redhat
redhatrhbk/keycloak-rhel9-operator:26.4-222026-08-05redhat
redhatrhbk-openshift-rhel9/rhbk-openshift-rhel92026-08-05redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 18× in last 7d / 84× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed its CVE.org record (CNA or CISA ADP). An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

Showing the most recent 100 of 697 rows on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 597 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-13 16:51 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  2. 2026-11-12 17:17 UTCEchelonGraph re-scored
  3. 2026-11-12 17:17 UTCVendor advisory
  4. 2026-11-12 17:17 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  5. 2026-11-12 16:33 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  6. 2026-11-11 16:38 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  7. 2026-11-11 16:37 UTCEchelonGraph re-scored
  8. 2026-11-11 16:37 UTCVendor advisory
  9. 2026-11-11 16:37 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  10. 2026-11-10 16:42 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  11. 2026-11-10 15:57 UTCEchelonGraph re-scored
  12. 2026-11-10 15:57 UTCVendor advisory
  13. 2026-11-10 15:57 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  14. 2026-11-09 16:34 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  15. 2026-11-09 15:17 UTCEchelonGraph re-scored
  16. 2026-11-09 15:17 UTCVendor advisory
  17. 2026-11-09 15:17 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  18. 2026-11-08 16:38 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  19. 2026-11-08 14:37 UTCEchelonGraph re-scored
  20. 2026-11-08 14:37 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  21. 2026-11-07 16:38 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  22. 2026-11-07 13:57 UTCEchelonGraph re-scored
  23. 2026-11-07 13:57 UTCVendor advisory
  24. 2026-11-07 13:57 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  25. 2026-11-06 16:36 UTCEPSS rescoreEPSS 0.3% · 24th percentile
Show 75 more
  1. 2026-11-06 13:17 UTCEchelonGraph re-scored
  2. 2026-11-06 13:17 UTCVendor advisory
  3. 2026-11-06 13:17 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  4. 2026-11-05 16:36 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  5. 2026-11-05 12:38 UTCEchelonGraph re-scored
  6. 2026-11-05 12:38 UTCVendor advisory
  7. 2026-11-05 12:38 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  8. 2026-11-04 16:34 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  9. 2026-11-04 11:58 UTCEchelonGraph re-scored
  10. 2026-11-04 11:58 UTCVendor advisory
  11. 2026-11-04 11:58 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  12. 2026-11-03 16:47 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  13. 2026-11-03 11:18 UTCEchelonGraph re-scored
  14. 2026-11-03 11:18 UTCVendor advisory
  15. 2026-11-03 11:18 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  16. 2026-11-02 16:44 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  17. 2026-11-02 10:38 UTCEchelonGraph re-scored
  18. 2026-11-02 10:38 UTCVendor advisory
  19. 2026-11-02 10:38 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  20. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  21. 2026-11-01 09:57 UTCEchelonGraph re-scored
  22. 2026-11-01 09:57 UTCVendor advisory
  23. 2026-11-01 09:57 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  24. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  25. 2026-10-31 09:18 UTCEchelonGraph re-scored
  26. 2026-10-31 09:18 UTCVendor advisory
  27. 2026-10-31 09:18 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  28. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  29. 2026-10-30 08:38 UTCEchelonGraph re-scored
  30. 2026-10-30 08:38 UTCVendor advisory
  31. 2026-10-30 08:38 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  32. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  33. 2026-10-29 07:59 UTCEchelonGraph re-scored
  34. 2026-10-29 07:59 UTCVendor advisory
  35. 2026-10-29 07:59 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  36. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  37. 2026-10-28 07:19 UTCEchelonGraph re-scored
  38. 2026-10-28 07:19 UTCVendor advisory
  39. 2026-10-28 07:19 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  40. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  41. 2026-10-27 06:40 UTCEchelonGraph re-scored
  42. 2026-10-27 06:40 UTCVendor advisory
  43. 2026-10-27 06:40 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  44. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  45. 2026-10-26 02:27 UTCEchelonGraph re-scored
  46. 2026-10-26 02:27 UTCVendor advisory
  47. 2026-10-26 02:27 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  48. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  49. 2026-10-25 14:46 UTCEchelonGraph re-scored
  50. 2026-10-25 01:47 UTCEchelonGraph re-scored
  51. 2026-10-25 01:47 UTCVendor advisory
  52. 2026-10-25 01:47 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  53. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  54. 2026-10-24 01:08 UTCEchelonGraph re-scored
  55. 2026-10-24 01:08 UTCVendor advisory
  56. 2026-10-24 01:08 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  57. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  58. 2026-10-23 00:26 UTCEchelonGraph re-scored
  59. 2026-10-23 00:26 UTCVendor advisory
  60. 2026-10-23 00:26 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  61. 2026-10-22 16:33 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  62. 2026-10-21 23:45 UTCEchelonGraph re-scored
  63. 2026-10-21 23:45 UTCVendor advisory
  64. 2026-10-21 23:45 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  65. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  66. 2026-10-20 23:05 UTCEchelonGraph re-scored
  67. 2026-10-20 23:05 UTCVendor advisory
  68. 2026-10-20 23:05 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  69. 2026-10-20 16:32 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  70. 2026-10-19 22:25 UTCEchelonGraph re-scored
  71. 2026-10-19 22:25 UTCVendor advisory
  72. 2026-10-19 22:25 UTCGHSA enrichmentGHSA-vj6m-hv26-qx79 · GitHub severity HIGH · GitHub CVSS 7.4
  73. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.3% · 22nd percentile
  74. 2026-10-18 21:20 UTCEchelonGraph re-scored
  75. 2026-10-18 21:20 UTCVendor advisory

Frequently asked(5)

What is CVE-2026-16442?
CVE-2026-16442 is a critical-severity vulnerability; its CVE record was published on August 5, 2026. A flaw was found in the SAML broker component of Keycloak, which is used to manage identity federation and user authentication. The issue occurs because the IdP-initiated Single Sign-On endpoint fails to check if a provider is restricted to account linking only. This allows an attacker with control…
When was CVE-2026-16442 made public?
CVE-2026-16442 was made public on August 5, 2026: that is the date its CVE record's CNA, Red Hat, Inc., gives for when the vulnerability was made public. The CVE record itself was published on August 5, 2026. EchelonGraph's copy of the record carries a last-modified date of August 31, 2026; the record at its source may have been updated since.
Is CVE-2026-16442 actively exploited?
CVE-2026-16442 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (24th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-16442?
CVE-2026-16442 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-16442?
A fix for CVE-2026-16442 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-16442 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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