CVE-2026-77998Network attack vector

Unauthenticated account takeover via signature error acceptance

Published Aug 25, 2026 · Updated Aug 26, 2026

Authentication bypass in affected miniOrange Joomla SSO extensions allows remote attackers to log in as any existing user via a crafted SAMLResponse. The mo_saml_validate_signature() function loosely tests openssl_verify()'s tri-state return, treating the -1 error produced by a malformed signature as successful verification. A reachable, configured SSO flow and a NameID matching an existing Joomla user are required; targeting an administrator grants administrative access.

CVSS severity10.0
Critical
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in affected miniOrange Joomla SSO extensions allows remote attackers to log in as any existing user via a crafted SAMLResponse. The mo_saml_validate_signature() function loosely tests openssl_verify()'s tri-state return, treating the -1 error produced by a malformed signature as successful verification. A reachable, configured SSO flow and a NameID matching an existing Joomla user are required; targeting an administrator grants administrative access.

The record

CVE
CVE-2026-77998
Published
Aug 25, 2026
Updated
Aug 26, 2026
Vendor
miniOrange
Product
SAML SSO Free for Joomla
Classifications
CWE-639, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.0.0-11.0.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

miniOrange · SAML SSO Free for Joomlaversion=1.0.0-11.0.1
miniOrange · Single Sign On for Educational Institutesversion=1.0.0-1.2.1
miniOrange · SAML SP Single Sign On – Login with ADFSversion=1.0.0-6.3.0
miniOrange · OAuth Single Sign-On - OIDC SSO | Login with Azure ADversion=1.0.0-1.2.1
miniOrange · Login with Keycloak OAuth Single Sign-On (SSO) | Login with Keycloakversion=1.0.0-1.2.1
miniOrange · SAML SSO Basic for Joomlaversion=1.0.0-13.1.0
miniOrange · SAML SSO Premium for Joomlaversion=1.0.0-34.1.0
miniOrange · SAML SSO Standard for Joomlaversion=1.0.0-24.1.0
miniOrange · SAML SSO login with Google Appsversion=1.0.0-6.3.0
miniOrange · SAML SSO Enterprise for Joomlaversion=1.0.0-44.1.0

Published CVSS scores

10.0Joomla CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-639Authorization Bypass Through User-Controlled Key
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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