Security News > 2023 > September > Cisco urges admins to fix IOS software zero-day exploited in attacks

Cisco warned customers on Wednesday to patch a zero-day IOS and IOS XE software vulnerability targeted by attackers in the wild.
"An attacker could exploit this vulnerability by either compromising an installed key server or modifying the configuration of a group member to point to a key server that is controlled by the attacker," Cisco explained in a security advisory published on Wednesday.
The zero-day bug impacts all Cisco products running a vulnerable IOS or IOS XE software version with either the GDOI or G-IKEv2 protocol enabled.
Meraki products and those running IOS XR and NX-OS software are not exposed to attacks using CVE-2023-20109 exploits.
On Wednesday, Cisco also issued security patches for a critical vulnerability in the Security Assertion Markup Language APIs of Catalyst SD-WAN Manager network management software.
Cisco warns of VPN zero-day exploited by ransomware gangs.
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Related Vulnerability
DATE | CVE | VULNERABILITY TITLE | RISK |
---|---|---|---|
2023-09-27 | CVE-2023-20109 | Out-of-bounds Write vulnerability in Cisco IOS A vulnerability in the Cisco Group Encrypted Transport VPN (GET VPN) feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker who has administrative control of either a group member or a key server to execute arbitrary code on an affected device or cause the device to crash. This vulnerability is due to insufficient validation of attributes in the Group Domain of Interpretation (GDOI) and G-IKEv2 protocols of the GET VPN feature. | 6.6 |