CVE-2026-34182: CMS AuthEnvelopedData Processing May Accept Forged Messages

CSIRTS triage

What

The vulnerability may allow CMS AuthEnvelopedData processing to accept forged messages.

Who is affected

Deployments using CMS for AuthEnvelopedData processing.

Urgency

Remediation is critical urgency due to the critical severity rating.

Action

Apply the latest patches for CMS.

AI-assisted analysis generated from the source advisory — verify against the original.

Details

Source

Microsoft Security Response Center (INTL · vendor-psirt · site)

Severity

critical — CVSS 9.1

Published

2026-08-06

Exploitation

Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-34182

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

• Low exploitation riskCVE-2026-341820.37% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 30% of all EPSS-scored CVEs.

Referenced CVEs

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

• high[UPDATE] [high] OpenSSL: Multiple Vulnerabilitiescert-bund
• high[NEW] [high] IBM App Connect Enterprise: Multiple vulnerabilitiescert-bund
• high[NEW] [high] Oracle Solaris third-party components: Multiple vulnerabilitiescert-bund
• unknownMultiple vulnerabilities in Oracle Database Server (July 23, 2026)cert-fr-avis

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