--- cve: "CVE-2018-11518" severity: "LOW" cvss: 3.1 epss: "1.4%" vendor: "n/a" kev: false exploited: false published: "2018-05-30 20:29:00" tags: [cve, security, low] source: tsecurity.de CVE-Dossier exported: "2026-09-08T20:59:39+02:00" --- # CVE-2018-11518 > 3.1 LOW ## Beschreibung A vulnerability allows a phreaking attack on HCL legacy IVR systems that do not use VoIP. These IVR systems rely on various frequencies of audio signals; based on the frequency, certain commands and functions are processed. Since these frequencies are accepted within a phone call, an attacker can record these frequencies and use them for service activations. This is a request-forgery issue when the required series of DTMF signals for a service activation is predictable (e.g., the IVR system does not speak a nonce to the caller). In this case, the IVR system accepts an activation request from a less-secure channel (any loudspeaker in the caller's physical environment) without verifying that the request was intended (it matches a nonce sent over a more-secure channel to the caller's earpiece). ## Referenzen - - - - --- _Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2018-11518) ยท Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_