Improper input validation in Cisco Secure Email
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
A vulnerability in the zip decompression engine of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass content filters that are configured on an affected device. The vulnerability is due to improper handling of password-protected zip files. An attacker could exploit this vulnerability by sending a malicious file inside a crafted zip-compressed file to an affected device. A successful exploit could allow the attacker to bypass configured content filters that would normally drop the email.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Cisco | Cisco Secure Email | N/A | — | No fix listed | CNA |
- Cisco Secure Email VendorCisco Affected N/A Fixed in — No fix listed CNA
CPE configurations NVD · 8
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:* | before 13.5.2 | Vulnerable | Cisco |
| cpe:2.3:h:cisco:email_security_appliance_c170:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:email_security_appliance_c190:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:email_security_appliance_c380:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:email_security_appliance_c390:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:email_security_appliance_c680:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:email_security_appliance_c690:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
| cpe:2.3:h:cisco:email_security_appliance_c690x:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Cisco |
- cpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:* Versions before 13.5.2 Vulnerable ·Cisco
- cpe:2.3:h:cisco:email_security_appliance_c170:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:email_security_appliance_c190:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:email_security_appliance_c380:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:email_security_appliance_c390:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:email_security_appliance_c680:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:email_security_appliance_c690:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
- cpe:2.3:h:cisco:email_security_appliance_c690x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2020-26082
- 2026-10-03 Alias added: GHSA-3hxf-p384-rmc6
- 2026-10-29 EPSS moved to the 50th–90th percentile
References
Advisory 1
More Cisco Asyncos vulnerabilities
- TI-2026-74174 Arbitrary file write in Cisco Secure Email Gateway via AMP feature KEVCVSS 3.1CRITICAL 9.8
- TI-2026-53489 Cisco Secure Email Gateway SQL Injection Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2025-14683 Cisco Secure Email Gateway and Cisco Secure Email and Web Manager Remote Command Execution Vulnerability KEVCVSS 3.1CRITICAL 10.0
- TI-2021-13698 Cisco Web Security Appliance Proxy Service Denial of Service Vulnerability CVSS 3.1HIGH 8.6
- TI-2018-11020 Cisco Email Security Appliance URL Filtering Denial of Service Vulnerability CVSS 3.1HIGH 8.6
- TI-2019-01567 Cisco Email Security Appliance Denial of Service Vulnerability CVSS 3.1HIGH 8.6
Sources
- CVE-2020-26082 · CVE Program
- CVE-2020-26082 · NVD
- FIRST EPSS
- GHSA-3hxf-p384-rmc6 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences