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Fencer Intel
critical 9.8

CVE-2026-104056 json

CVE-2026-104056

published last mo. modified last mo. also EUVD-2026-91003

cvss
9.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 9%
public exploits
0
none known

Summary

Authlib version 1.7.2 and below contains a vulnerability where discovery JSON metadata is cached without validation or issuer-origin binding. This allows a poisoned discovery response to replace all endpoint values with attacker-controlled values rather than endpoint URLs that share the origin of the configured server metadata URL.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-104056 updated cvss 5.9

authlib: authlib: Information disclosure via unvalidated discovery metadata

  • Red Hat Exploit Intelligence exploit-intelligence/vulnerability-analysis-rhel9
    affected: workaround, no fix planned “Out of support scope”
  • Red Hat Lightspeed Core lightspeed-core/lightspeed-stack-rhel9 Red Hat Migration Toolkit for Applications 8 mta/mta-solution-server-rhel9 Red Hat OpenShift Lightspeed openshift-lightspeed/lightspeed-agentic-sandbox-rhel9 Red Hat Ansible Automation Platform 2 ansible-automation-platform-26/lightspeed-chatbot-rhel9, ansible-automation-platform-27/lightspeed-chatbot-rhel9 Red Hat Enterprise Linux command line assistant rhel-cla/rhel-knowledge-bridge-rhel10 Red Hat OpenShift Virtualization 4 openshift-virtualization/konflux-builds/v4-22/ocp-virt-validation-checkup-rhel9
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Quay 3 quay/quay-rhel8, quay/quay-rhel9
    affected: workaround, no fix available, no fix planned “Out of support scope”
  • Red Hat Satellite 6 satellite/foreman-mcp-server-rhel9
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Hardened Images jaeger 2.20.0-0.11.hum1
    not affected: component not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
total
Assessed
last mo.

Exploit prediction

0.20% chance of exploitation in the next 30 days, higher than 9% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • uziii2208.github.io https://uziii2208.github.io/post/cve-2026-104056/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CISA ADP 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Authlib Authlib

Classification

Weakness
  • CWE-345 Insufficient Verification of Data Authenticity
  • CWE-346 Origin Validation Error
  • CWE-829 Inclusion of Functionality from Untrusted Control Sphere

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.