CVE-2025-20153
Cisco ESA mail Bypass
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Cisco ESA mail Bypass
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.
- Record
CVE-2025-20153- CVSS 3.1
- 5.8 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N - Weakness
- CWE-284
- Updated
- 2026-11-02
EUVDEUVD-2025-4671
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.
- Record
EUVD-2025-4671- CVSS 3.1
- 5.8 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-9ppw-7p8w-h9g2
A vulnerability in the email filtering mechanism of Cisco Secure Email Gateway could allow an...
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.
- Record
GHSA-9ppw-7p8w-h9g2- CVSS 3.1
- 5.8 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N - Weakness
- CWE-284
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2025-20153- CVSS 3.1
- 5.8 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N - CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-284
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-20153 is a medium vulnerability (CVSS 5.8) in Cisco Secure Email, published February 19, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.36%, the 30th percentile. No source names a fixed version.