MEDIUM✓ PATCH🇵🇱 Wersja polska

CVE-2021-34705

CVSS 5.3v3.1pub. 2021-09-23upd. 2025-10-30

A vulnerability in the Voice Telephony Service Provider (VTSP) service of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass configured destination patterns and dial arbitrary numbers. This vulnerability is due to insufficient validation of dial strings at Foreign Exchange Office (FXO) interfaces. An attacker could exploit this vulnerability by sending a malformed dial string to an affected device via either the ISDN protocol or SIP. A successful exploit could allow the attacker to conduct toll fraud, resulting in unexpected financial impact to affected customers.

CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
  • Cisco IOS

    OS
    Cisco
    12.3\(10\)12.3\(7\)xm12.3\(7\)xr12.3\(7\)xr112.3\(7\)xr212.3\(7\)xr312.3\(7\)xr412.3\(7\)xr512.3\(7\)xr612.3\(7\)xr712.3\(8\)ja212.3\(8\)jea112.3\(8\)jea212.3\(8\)jea312.3\(8\)jeb+ 85 more
🟢
PATCH AVAILABLE
Vendor update available. Deploy in standard maintenance cycle.
CWE
References

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