CVE-2026-20355
Last modified
CVE-2026-20355 is a medium-severity vulnerability rated 5.9/10 on the CVSS scale. 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.
Description
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.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Cisco | Cisco Secure Email | 14.0.0-698; 13.5.1-277; 13.0.0-392; 14.2.0-620; 13.0.5-007; 13.5.4-038; 14.2.1-020; 14.3.0-032; 15.0.0-104; 15.0.1-030; 15.5.0-048; 15.5.1-055; 15.5.2-018; 16.0.0-050; 15.0.3-002; 16.0.0-054; 15.5.3-022; 16.0.1-017; 15.5.4-012; 16.0.4-016; 15.0.5-016; 16.0.2-112; 16.0.3-044; 16.5.0-780 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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