Secure Email Gateway
CVE-2025-20153
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Access control enforcement
MITRE ATT&CK
1 technique across 1 tactic: Defense Evasion The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 5.8 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. EPSS exploitation probability: 0.09%. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Mar 28, 2026
A vulnerability in the email filtering mechanism of Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to bypass the configured rules and allow emails that should have been. Rated medium severity (CVSS 5.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified under CWE-284. A vulnerability in the email filtering mechanism of Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to bypass the configured rules and allow emails that should have been denied to flow through an affected device. This vulnerability is due to improper handling of email that passes through an affected device. An attacker could exploit this vulnerability by sending a crafted email through the affected device. A successful exploit could allow the attacker to bypass email filters on the affected device. Affected products include: Cisco Secure Email Gateway.
Know when Secure Email Gateway gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
A vulnerability in the email filtering mechanism of Cisco Secure Email Gateway could allow an unauthenticated, remote attacker to bypass the configured rules and allow emails that should have been denied to flow through an affected device.
This vulnerability is due to improper handling of email that passes through an affected device. An attacker could exploit this vulnerability by sending a crafted email through the affected device. A successful exploit could allow the attacker to bypass email filters on the affected device.
Executive ViewAI
CVE-2025-20153 presents moderate security risk, a improper access control vulnerability rated CVSS 5.8. Exploitation could compromise the security of affected deployments. Organizations should apply vendor updates when available and monitor for exploitation.
Apply vendor patch. If patching is delayed: restrict network access and enable monitoring.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Affected Products (CPE)CVE.org
More in Secure Email Gateway
View allSecure Email Gateway from Cellopoint has Buffer Overflow Vulnerability in authentication process. Rated critical severit
A vulnerability in the content scanning and message filtering features of Cisco Secure Email Gateway could allow an unau
The SMTP Listener of Secure Email Gateway from Cellopoint does not properly validate user input, leading to a Buffer Ove
Remote code execution in SEPPmail Secure Email Gateway versions prior to 15.0.2.1 enables unauthenticated attackers to e
Authorization bypass in SEPPmail Secure Email Gateway versions prior to 15.0.4 enables remote unauthenticated attackers
Remote unauthenticated attackers can read arbitrary local files and trigger deletion of targeted files in SEPPmail Secur
Command injection in SEPPmail Secure Email Gateway before version 15.0.7 enables authenticated administrators to execute
Remote code execution in SEPPmail Secure Email Gateway versions before 15.0.4 allows unauthenticated attackers to execut
SEPPmail Secure Email Gateway before version 15.0.3 allows attackers to bypass subject sanitization and forge security t
SEPPmail Secure Email Gateway before version 15.0.3 fails to properly authenticate inner messages within S/MIME-encrypte
Account takeover in SEPPmail Secure Email Gateway versions before 15.0.3 allows unauthenticated attackers to reset victi
SEPPmail Secure Email Gateway before version 15.0.3 allows remote attackers to bypass subject line sanitization controls
GitHub PoC
Exploit-DB