What is CVE-2021-34705?

CVE-2021-34705 is a medium-severity vulnerability in Cisco iOS, classified under CWE-232. CVSS score: 5.3/10. Published 2021-09-23.

How severe is CVE-2021-34705?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Cisco iOS

CVE-2021-34705

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.

EPSS: 0.010 (60.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

Affected products

Cisco Ios — versions n/a
Cisco Ios — versions 12.3\(13a\)bc3, 12.4(15)sw5, 12.4(9)t
Cisco Ios_xe — versions 3.7.0bs, 3.7.0s, 3.7.0xas

Weakness classification (CWE)

CWE-232

References

psirt@cisco.com (x_refsource_CISCO, vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2021-34705?: CVE-2021-34705 is a medium-severity vulnerability in Cisco iOS, classified under CWE-232. CVSS score: 5.3/10. Published 2021-09-23.
How severe is CVE-2021-34705?: Medium severity. CVSS v3 base score is 5.3 out of 10.