CVE-2026-20058
Cisco Secure Firewall Threat Defense Software Snort 3 Visual Basic for Application Denial of Service Vulnerability
Multiple Cisco products are affected by vulnerabilities in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash.
These vulnerabilities are due to improper error checking when decompressing VBA data. An attacker could exploit these vulnerabilities by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to unexpectedly restart, causing a DoS condition.
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
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
Cisco Secure Firewall Threat Defense Software Snort 3 Visual Basic for Application Denial of Service Vulnerability
Multiple Cisco products are affected by vulnerabilities in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash.
These vulnerabilities are due to improper error checking when decompressing VBA data. An attacker could exploit these vulnerabilities by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to unexpectedly restart, causing a DoS condition.
- Record
CVE-2026-20058- CVSS 3.1
- 5.8 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L - Weakness
- CWE-786
- Updated
- 2026-11-02
EUVDEUVD-2026-9462
Multiple Cisco products are affected by vulnerabilities in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash.
These vulnerabilities are due to improper error checking when decompressing VBA data. An attacker could exploit these vulnerabilities by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to unexpectedly restart, causing a DoS condition.
- Record
EUVD-2026-9462- CVSS 3.1
- 5.8 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-q3px-v248-7pc3
Multiple Cisco products are affected by vulnerabilities in the Snort 3 VBA feature that could...
Multiple Cisco products are affected by vulnerabilities in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash.
These vulnerabilities are due to improper error checking when decompressing VBA data. An attacker could exploit these vulnerabilities by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to unexpectedly restart, causing a DoS condition.
- Record
GHSA-q3px-v248-7pc3- CVSS 3.1
- 5.8 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L - Weakness
- CWE-786
- Updated
- 2026-11-02
NVD
Multiple Cisco products are affected by vulnerabilities in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash.
These vulnerabilities are due to improper error checking when decompressing VBA data. An attacker could exploit these vulnerabilities by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to unexpectedly restart, causing a DoS condition.
- Record
CVE-2026-20058- CVSS 3.1
- 5.8 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L - Weakness
- CWE-786
- Updated
- 2026-11-02
OSV
Multiple Cisco products are affected by vulnerabilities in the Snort 3 VBA feature that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to crash.
These vulnerabilities are due to improper error checking when decompressing VBA data. An attacker could exploit these vulnerabilities by sending crafted VBA data to the Snort 3 Detection Engine on the targeted device. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to unexpectedly restart, causing a DoS condition.
- Record
CVE-2026-20058- CVSS 3.1
- 5.8 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-20058 is a medium vulnerability (CVSS 5.8) in Cisco Secure Firewall Threat Defense, published March 4, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.45%, the 39th percentile. No source names a fixed version.