CVE-2026-20341 json
Cisco Secure Firewall Management Center Software sftunnel Deserialization Root Command Execution Vulnerability
published 2026-09-16 53 d ago modified 2026-09-18 52 d ago also EUVD-2026-81110
- cvss
- 9.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 49%
- public exploits
- 0
- none known
Summary
A vulnerability in the sftunnel inter-device communication protocol of Cisco Secure FMC Software could allow an authenticated, remote attacker to obtain root privileges.
This vulnerability is due to unsecured deserialization of untrusted data over the sftunnel management connection. An attacker could exploit this vulnerability by sending crafted sftunnel remote procedure calls (RPCs). A successful exploit could allow the attacker to gain root privileges on a device that is running Cisco Secure FMC Software and its high-availability peer. To exploit this vulnerability, the attacker must have valid administrative credentials on a managed Cisco FTD device.
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 53 d ago
Exploit prediction
0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H |
Affected products
- Cisco Cisco Secure Firewall Management Center (FMC)
Classification
- Weakness
-
- CWE-502 Deserialization of Untrusted Data
References
Sources
- CVE List CVE-2026-20341
- NVD CVE-2026-20341
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