Legacy Ivr Firmware
CVE-2018-11518
HIGH
Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
1DescriptionNVD
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).
AnalysisAI
A vulnerability allows a phreaking attack on HCL legacy IVR systems that do not use VoIP. Rated high severity (CVSS 8.1), this vulnerability is remotely exploitable, no authentication required. No vendor patch available.
Technical ContextAI
This vulnerability is classified under CWE-20. 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). Affected products include: Hcltech Legacy Ivr Firmware.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Same weakness CWE-20 – Improper Input Validation
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External POC / Exploit Code
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