CVE-2026-44203Network attack vector

Pre-auth reflected XSS via unencoded form_post parameters

Published Sep 15, 2026 · Updated Sep 15, 2026

Reflected XSS in OpenAM 13.0.0 through 16.0.6 allows remote attackers to execute script via crafted authorization requests. The authorization endpoint passes user-supplied parameters to FormPostResponse.ftl and checkSession.ftl without sufficient HTML encoding. Exploitation requires inducing a user to open the request; injected script runs with OpenAM-origin privileges in the user's browser.

CVSS severity9.3
Critical
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in OpenAM 13.0.0 through 16.0.6 allows remote attackers to execute script via crafted authorization requests. The authorization endpoint passes user-supplied parameters to FormPostResponse.ftl and checkSession.ftl without sufficient HTML encoding. Exploitation requires inducing a user to open the request; injected script runs with OpenAM-origin privileges in the user's browser.

The record

CVE
CVE-2026-44203
Published
Sep 15, 2026
Updated
Sep 15, 2026
Vendor
Open Identity Platform
Product
OpenAM
Classifications
CWE-79, T1566.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 15, 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=< 16.1.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Open Identity Platform · OpenAMversion=< 16.1.1

Published CVSS scores

9.3GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

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.

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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-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1566.002Spearphishing Link

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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