CVE-2021-34705

mediumPriorität · verfolgen · 21EPSS 0.010 · 63. PerzentilEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.01% (63rd) EPSS
CVSS 4.3 · medium
Is it mine?
3,388 products
Prüfe deine Angriffsfläche
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · bewertet 2026-10-27

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.

01

Behebungen

Hersteller-Fix, Mitigation oder Workaround, wie von den Quellen veröffentlicht.

Ein Hersteller-Fix ist verfügbar.

02

cvss

Technischer Schweregrad, 0–10. Eine Zeile je Quelle.

5.3
010

Basiswert 0–10 · höher = schwerwiegender · Vektor überfahren zum Auflösen

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USAusnutzbarkeit 8.6 · Auswirkung 2.9
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nprimary · NVD / NIST USAusnutzbarkeit 3.9 · Auswirkung 1.4
v3.15.3mediumAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · FSTEC (BDU) RU
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · ENISA EU
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · psirt@cisco.com USAusnutzbarkeit 3.9 · Auswirkung 1.4
v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:Nsecondary · Cisco PSIRT US
03

schwächen

Die CWE-Schwächeklassen, zu denen dies gehört.

CWE-232USCWE-232US
04

betroffene Produkte (3,388)

Betroffene Produkte und Versionsbereiche.

20 von 3,388 angezeigt
05

Advisories (1)

Hersteller- und Ökosystem-Meldungen dazu.

  • cisco-sa-fxo-pattern-bypass-jUXgygYvCisco IOS and IOS XE Software FXO Interface Destination Pattern Bypass Vulnerability2021-09-22csaf · cisco_csafUS

    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. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the September 2021 release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: September 2021 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication. ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74581"]

06

auch bekannt als (4)

Weitere Namen und Kennungen dieser Entität.

07

quellen

Welche Quellen diesen Datensatz belegen und wann.

cnnvdenisa_euvdfstec_bducisco_csafNVDCVE.orgMITRE
veröffentlicht 2021-09-23geändert 2026-06-17
08

Referenzen (6)

Externe Belege — Patches, Meldungen, Analysen.

scry

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