Description
A vulnerability in the AnyConnect SSL VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to send packets with another VPN user's source IP address. This vulnerability is due to improper validation of the packet's inner source IP address after decryption. An attacker could exploit this vulnerability by sending crafted packets through the tunnel. A successful exploit could allow the attacker to send a packet impersonating another VPN user's IP address. It is not possible for the attacker to receive return packets.
Affected products
cisco: adaptive security appliance software; cisco: secure firewall threat defense
References2
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAd… Vendor Advisory
- sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAd… Vendor Advisory
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 36 · as of 5 November 2026
- CWE
- CWE-346
Could this be exploited in your environment?
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