CVE-2021-34705

Medium

Description

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.

SeverityMedium
CVSS5.3
Exploit probability—
ProductCisco Ios
PublishedSep 23, 2021
First seenSep 23, 2021
Weakness typeCWE-232CWE-232

How to fix

Affected products

ProductAffected versionsFixed in
cisco ios12.3\(7\)xm, 12.3\(7\)xr, 12.3\(7\)xr1, 12.3\(7\)xr2, 12.3\(7\)xr3, 12.3\(7\)xr4, 12.3\(7\)xr5, 12.3\(7\)xr6, 12.3\(7\)xr7, 12.3\(8\)ja2, 12.3\(8\)jea1, 12.3\(8\)jea2, 12.3\(8\)jea3, 12.3\(8\)jeb, 12.3\(8\)jeb1, 12.3\(8\)jec3, 12.3\(8\)jed1, 12.3\(8\)jee, 12.3\(8\)jk, 12.3\(8\)jk1, 12.3\(8\)t, 12.3\(8\)t0a, 12.3\(8\)t1, 12.3\(8\)t2, 12.3\(8\)t3, 12.3\(8\)t4, 12.3\(8\)t5, 12.3\(8\)t6, 12.3\(8\)t7, 12.3\(8\)t8, 12.3\(8\)t9, 12.3\(8\)t10, 12.3\(8\)t11, 12.3\(8\)xu, 12.3\(8\)xu1, 12.3\(8\)xu2, 12.3\(8\)xu3, 12.3\(8\)xu4, 12.3\(8\)xu5, 12.3\(8\)xw, 12.3\(8\)xw1, 12.3\(8\)xw1a, 12.3\(8\)xw1b, 12.3\(8\)xw2, 12.3\(8\)xw3, 12.3\(8\)xx, 12.3\(8\)xx1, 12.3\(8\)xx2, 12.3\(8\)xx2a, 12.3\(8\)xx2b, 12.3\(8\)xx2c, 12.3\(8\)xx2d, 12.3\(8\)xx2e, 12.3\(8\)xy, 12.3\(8\)xy1, 12.3\(8\)xy2, 12.3\(8\)xy3, 12.3\(8\)xy4, 12.3\(8\)xy5, 12.3\(8\)xy6, 12.3\(8\)xy7, 12.3\(8\)yc, 12.3\(8\)yc1, 12.3\(8\)yc2, 12.3\(8\)yc3, 12.3\(8\)yd, 12.3\(8\)yd1, 12.3\(8\)yg, 12.3\(8\)yg1, 12.3\(8\)yg2, 12.3\(8\)yg3, 12.3\(8\)yg4, 12.3\(8\)yg5, 12.3\(8\)yg6, 12.3\(8\)yg7, 12.3\(8\)yi, 12.3\(8\)yi1, 12.3\(8\)yi2, 12.3\(8\)yi3, 12.3\(8\)za, 12.3\(8\)za1, 12.3\(9\), 12.3\(9\)m0, 12.3\(9\)m1, 12.3\(9a\), 12.3\(9a\)bc, 12.3\(9a\)bc1, 12.3\(9a\)bc2, 12.3\(9a\)bc3, 12.3\(9a\)bc4, 12.3\(9a\)bc5, 12.3\(9a\)bc6, 12.3\(9a\)bc7, 12.3\(9a\)bc8, 12.3\(9a\)bc9, 12.3\(9b\), 12.3\(9c\), 12.3\(9d\), 12.3\(9e\), 12.3\(10\), 12.3\(10a\), 12.3\(10a\)m0, 12.3\(10b\), 12.3\(10c\), 12.3\(10d\), 12.3\(10e\), 12.3\(10f\), 12.3\(11\)ja, 12.3\(11\)ja1, 12.3\(11\)ja2, 12.3\(11\)ja3, 12.3\(11\)ja4, 12.3\(11\)jx, 12.3\(11\)jx1, 12.3\(11\)t, 12.3\(11\)t1, 12.3\(11\)t2, 12.3\(11\)t2a, 12.3\(11\)t3, 12.3\(11\)t4, 12.3\(11\)t5, 12.3\(11\)t6, 12.3\(11\)t7, 12.3\(11\)t8, 12.3\(11\)t9, 12.3\(11\)t10, 12.3\(11\)t11, 12.3\(11\)t12, 12.3\(11\)to3, 12.3\(11\)xl, 12.3\(11\)xl1, 12.3\(11\)xl2, 12.3\(11\)xl3, 12.3\(11\)yf, 12.3\(11\)yf1, 12.3\(11\)yf2, 12.3\(11\)yf3, 12.3\(11\)yf4, 12.3\(11\)yj, 12.3\(11\)yk, 12.3\(11\)yk1, 12.3\(11\)yk2, 12.3\(11\)yk3, 12.3\(11\)yl, 12.3\(11\)yl1, 12.3\(11\)yl2, 12.3\(11\)yr, 12.3\(11\)yr1, 12.3\(11\)ys, 12.3\(11\)ys1, 12.3\(11\)ys2, 12.3\(11\)yz, 12.3\(11\)yz1, 12.3\(11\)yz2, 12.3\(11\)zb, 12.3\(11\)zb1, 12.3\(11\)zb2, 12.3\(12\), 12.3\(12a\), 12.3\(12b\), 12.3\(12c\), 12.3\(12d\), 12.3\(12e\), 12.3\(13\), 12.3\(13a\), 12.3\(13a\)bc, 12.3\(13a\)bc1, 12.3\(13a\)bc2, 12.3\(13a\)bc3, 12.3\(13a\)bc4, 12.3\(13a\)bc5, 12.3\(13a\)bc6, 12.3\(13b\), 12.3\(14\)t, 12.3\(14\)t1, 12.3\(14\)t2, 12.3\(14\)t3, 12.3\(14\)t4, 12.3\(14\)t5, 12.3\(14\)t6, 12.3\(14\)t7, 12.3\(14\)ym1, 12.3\(14\)ym2, 12.3\(14\)ym3, 12.3\(14\)ym4, 12.3\(14\)ym5, 12.3\(14\)ym6, 12.3\(14\)ym7, 12.3\(14\)ym8, 12.3\(14\)ym9, 12.3\(14\)ym10, 12.3\(14\)ym11, 12.3\(14\)ym12, 12.3\(14\)ym13, 12.3\(14\)yq, 12.3\(14\)yq1, 12.3\(14\)yq2, 12.3\(14\)yq3, 12.3\(14\)yq4, 12.3\(14\)yq5—

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.