Buffer under-read in Snort - CVE-2025-20359
Published: October 15, 2025
Vulnerability identifier: #VU117301
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2025-20359
CWE-ID: CWE-127
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a boundary error within the HTTP decoder when handling MIME fields. A remote attacker can send specially crafted HTTP packets through the channel that is monitored by the application and perform a denial of service (DoS) attack.
Affected software
Snort
Cisco Adaptive Security Appliance (ASA)
Cisco Firewall Threat Defense (FTD)
Cyber Vision
Cisco Secure Firewall Management Center (formerly Firepower Management Center, FMC)
Cisco Adaptive Security Appliance (ASA)
Cisco Firewall Threat Defense (FTD)
Cyber Vision
Cisco Secure Firewall Management Center (formerly Firepower Management Center, FMC)
How to mitigate CVE-2025-20359
Install updates from vendor's website.
Snort - update to 3.9.3.0
Cisco Firewall Threat Defense (FTD) - addressed in versions 7.4.3, 7.6.2, 7.7.10
Cisco Secure Firewall Management Center (formerly Firepower Management Center, FMC) - addressed in versions 7.4.3, 7.6.2, 7.7.10
Cisco Firewall Threat Defense (FTD) - addressed in versions 7.4.3, 7.6.2, 7.7.10
Cisco Secure Firewall Management Center (formerly Firepower Management Center, FMC) - addressed in versions 7.4.3, 7.6.2, 7.7.10