OpenText Advanced Authentication Server: Improper trust of untrusted data in logon

Summary

OpenText Advanced Authentication Server, a multi-factor authentication platform, trusts extraneous untrusted data in a way that lets an attacker reach functionality that should be restricted by access controls. The CNA describes it as a logon bypass, but the NVD entry was still awaiting analysis and the weakness classification differs between sources. The vendor advisories list the affected ranges; the attack is network-reachable and needs no privileges or user interaction according to the CVSS v4 vector.

Affected

• OpenText Advanced Authentication Server 6.4.0.0 through 6.4.3.8
• OpenText Advanced Authentication Server 6.5.0.0 through 6.5.0.10
• OpenText Advanced Authentication Server 6.6.0.0 through 6.6.1.0

Fixed in

Unconfirmed. Inferred from vendor advisory page titles, to be verified on the advisory:

• 6.4: 6.4.3.9
• 6.5: 6.5.0.11
• 6.6: 6.6.2

Workaround

Unknown. No vendor-published workaround was found; patching is the only documented remedy.

Exploitation

• VulDB states that no exploit is available.
• Not listed in CISA KEV according to a third-party tracker; CISA catalogue not checked directly.
• EPSS score is 0.25 % (percentile 16).
• No public proof of concept or in-the-wild exploitation reports were found.

Our recommendation

• Inventory all OpenText Advanced Authentication Server instances and their exact versions.
• Check whether any instance is reachable from the internet and restrict access where possible.
• Plan the upgrade to the fixed release listed in the vendor advisory and confirm the target version there.
• Monitor for CISA KEV listing and public proof-of-concept reports, and re-check the NVD entry once analysed.

Public exploits iAttack code is publicly available (PoC on GitHub, Metasploit or Exploit-DB).

PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.

Research sources

• OpenText Documentation Portal: Security improvements 6.6.2 (26.3.1) docs.microfocus.com
• OpenText Documentation Portal: Security improvements 6.4.3.9 docs.microfocus.com
• OpenText Documentation Portal: Security improvements 6.5.0.11 docs.microfocus.com
• VulDB entry CVE-2026-112256 vuldb.com
• Threatint CVE record CVE-2026-112256 cve.threatint.com
• Strix CVE-2026-112256 www.strix.ai

Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 03:55.