Oracle Identity Manager: Authentication bypass in OIM Legacy UI
Summary
Oracle Identity Manager versions 12.2.1.4.0 and 14.1.2.1.0 contain a vulnerability in the OIM Legacy UI component (CWE-287, improper authentication). A remote attacker with a low-privilege account and HTTP network access can compromise the product, with possible full takeover of Oracle Identity Manager. Oracle rates the flaw CVSS 8.8 and says it is easily exploitable.
Affected
- Oracle Identity Manager 12.2.1.4.0
- Oracle Identity Manager 14.1.2.1.0
- Oracle Identity Manager Connector 12.2.1.4.0 and 14.1.2.1.0 (listed in Oracle's October 2026 CPU matrix)
Fixed in
- Fixed in the Oracle October 2026 Critical Patch Update (released 20 October 2026)
- Specific patch numbers and fixed versions: Unknown. Obtain them from the Oracle advisory risk matrix or My Oracle Support.
Workaround
Unknown. No vendor workaround was found in the sources. Check the Oracle advisory for any configuration-based mitigation for the OIM Legacy UI component.
Exploitation
- Known exploited (CISA KEV): No
- Public proof of concept: None found
- EPSS score: Not available
- CISA SSVC: Exploitation none, automatable no, technical impact total
Our recommendation
- Identify whether Oracle Identity Manager is deployed, including via Oracle Access Manager or SSO setups.
- Apply the Oracle October 2026 Critical Patch Update, using the patch numbers from the Oracle advisory.
- Prioritise any instance reachable from the internet; restrict HTTP access to internal networks where possible.
- Review accounts with low privileges and monitor the OIM HTTP interfaces for unusual activity.
- Verify the NVD status and CWE mapping, as NVD showed Awaiting Analysis at the time of research.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Oracle Security Alert: October 2026 CPU www.oracle.com
- Oracle Security Blog: October 2026 CPU released blogs.oracle.com
- OpenCVE: CVE-2026-91259 app.opencve.io
- Vulners: Oracle CPU October 2026 matrix vulners.com
- Waratek: October 2026 CPU review waratek.com
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, 11:34.
Original description (NVD)
Vulnerability in the Oracle Identity Manager product of Oracle Fusion Middleware (component: OIM Legacy UI). Supported versions that are affected are 12.2.1.4.0 and 14.1.2.1.0. Easily exploitable vulnerability allows low privileged attacker with network access via HTTP to compromise Oracle Identity Manager. Successful attacks of this vulnerability can result in takeover of Oracle Identity Manager. CVSS 3.1 Base Score 8.8 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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