8.7
HIGH CVSS 4.0
CVE-2026-123543
OpenAM before 16.1.4 Unauthenticated DoS via Unbounded Java Deserialisation
Description

OpenAM before 16.1.4 contains a denial of service vulnerability that allows unauthenticated attackers to exhaust server resources by sending serialized Java data without size or structure limits. Attackers can send small crafted requests to remote SDK endpoints, classic login pages, or the administration console to block authentication, session validation and policy decisions.

INFO

Published Date :

Nov. 8, 2026, 2:16 a.m.

Last Modified :

Nov. 8, 2026, 2:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-123543 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Openidentityplatform openam
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH MITRE-CVE
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update OpenAM to version 16.1.4 or later to address resource exhaustion vulnerabilities.
  • Update OpenAM to version 16.1.4 or later.
  • Validate resource limits for Java data processing.
  • Monitor server resource utilization.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-123543.

URL Resource
https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-x7wr-5gxg-v833
https://www.vulncheck.com/advisories/openam-before-16.1.4-unauthenticated-dos-via-unbounded-java-deserialisation
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-123543 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-123543 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-123543 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Nov. 08, 2026

    Action Type Old Value New Value
    Added Description OpenAM before 16.1.4 contains a denial of service vulnerability that allows unauthenticated attackers to exhaust server resources by sending serialized Java data without size or structure limits. Attackers can send small crafted requests to remote SDK endpoints, classic login pages, or the administration console to block authentication, session validation and policy decisions.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-770
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/123xxx/CVE-2026-123543.json">CVE-2026-123543</a>
    Added Reference https://github.com/OpenIdentityPlatform/OpenAM/security/advisories/GHSA-x7wr-5gxg-v833
    Added Reference https://www.vulncheck.com/advisories/openam-before-16.1.4-unauthenticated-dos-via-unbounded-java-deserialisation
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.