CVE-2019-12664
A vulnerability in the Dialer interface feature for ISDN connections in Cisco IOS XE Software for Cisco 4000 Series Integrated Services Routers (ISRs) could allow an unauthenticated, adjacent attacker to pass IPv4 traffic through an ISDN channel prior…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.43%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A vulnerability in the Dialer interface feature for ISDN connections in Cisco IOS XE Software for Cisco 4000 Series Integrated Services Routers (ISRs) could allow an unauthenticated, adjacent attacker to pass IPv4 traffic through an ISDN channel prior to successful PPP authentication. The vulnerability is due to insufficient validation of the state of the PPP IP Control Protocol (IPCP). An attacker could exploit this vulnerability by making an ISDN call to an affected device and sending traffic through the ISDN channel prior to successful PPP authentication. Alternatively, an unauthenticated, remote attacker could exploit this vulnerability by sending traffic through an affected device that is configured to exit via an ISDN connection for which both the Dialer interface and the Basic Rate Interface (BRI) have been configured, but the Challenge Handshake Authentication Protocol (CHAP) password for PPP does not match the remote end. A successful exploit could allow the attacker to pass IPv4 traffic through an unauthenticated ISDN connection for a few seconds, from initial ISDN call setup until PPP authentication fails.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 1.43% probability · 71th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-200, CWE-287
- Affected
- cisco/ios xe
- Source
- psirt@cisco.com
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.