Cisco Unified Communications Products Security Hardening Release: October 2026
cisco-sa-voice-hardening-twgbH9e3
Summary
Multiple vulnerabilities in the Secure/Multipurpose Internet Mail Extensions (S/MIME) decryption functionality of Cisco Secure Email could allow an unauthenticated, remote attacker to recover plain text from encrypted email messages. These vulnerabilities are due to insufficient validation of message integrity. An attacker could exploit these vulnerabilities by using a machine-in-the-middle technique to intercept and modify traffic between email gateways.
A successful exploit could allow the attacker to obtain plaintext content from the encrypted communication. There are no workarounds that address these vulnerabilities. Security Impact Rating: Medium CVE: CVE-2026-20354,CVE-2026-20355
Products covered
A separate affected-products list was not included in the collected bulletin.
Remediation
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CVEs in this advisory 2
Update history
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