CVE-2021-34714

mediumPriorität · verfolgen · 30EPSS 0.004 · 33. PerzentilEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.39% (33rd) EPSS
CVSS 5.7 · medium
Is it mine?
1,182 products
Prüfe deine Angriffsfläche
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · bewertet 2026-10-26

A vulnerability in the Unidirectional Link Detection (UDLD) feature of Cisco FXOS Software, Cisco IOS Software, Cisco IOS XE Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload. This vulnerability is due to improper input validation of the UDLD packets. An attacker could exploit this vulnerability by sending specifically crafted UDLD packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: The UDLD feature is disabled by default, and the conditions to exploit this vulnerability are strict. An attacker must have full control of a directly connected device. On Cisco IOS XR devices, the impact is limited to the reload of the UDLD process.

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.

7.4
010

Basiswert 0–10 · höher = schwerwiegender · Vektor überfahren zum Auflösen⚠ Quellen uneinig · medium–high · 5.7–7.4

v2.05.7mediumAV:A/AC:M/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USAusnutzbarkeit 5.5 · Auswirkung 6.9
v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hprimary · NVD / NIST USAusnutzbarkeit 2.8 · Auswirkung 4
v3.17.4highAV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · ENISA EU
v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · psirt@cisco.com USAusnutzbarkeit 2.8 · Auswirkung 4
v3.16.8mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · Cisco PSIRT US
03

SSVC

Eine Handlungsentscheidung — aus Ausnutzung und Auswirkung.

Trackcoordinatorcisa_ssvcUS
04

schwächen

Die CWE-Schwächeklassen, zu denen dies gehört.

CWE-20USprimärCWE-20US
05

betroffene Produkte (1,182)

Betroffene Produkte und Versionsbereiche.

20 von 1,182 angezeigt
06

Advisories (1)

Hersteller- und Ökosystem-Meldungen dazu.

  • cisco-sa-ios-nxos-xr-udld-dos-W5hGHgtQMultiple Cisco Operating Systems Unidirectional Link Detection Denial of Service Vulnerability2021-09-22csaf · cisco_csafUS

    A vulnerability in the Unidirectional Link Detection (UDLD) feature of Cisco FXOS Software, Cisco IOS Software, Cisco IOS XE Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload. This vulnerability is due to improper input validation of the UDLD packets. An attacker could exploit this vulnerability by sending specifically crafted UDLD packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: The UDLD feature is disabled by default, and the conditions to exploit this vulnerability are strict. An attacker must have full control of a directly connected device. On Cisco IOS XR devices, the impact is limited to the reload of the UDLD process. 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"]

07

auch bekannt als (4)

Weitere Namen und Kennungen dieser Entität.

08

quellen

Welche Quellen diesen Datensatz belegen und wann.

cnnvdenisa_euvdfstec_bducisco_csafNVDCVE.orgMITRE
veröffentlicht 2021-09-23geändert 2026-06-17
10

Referenzen (6)

Externe Belege — Patches, Meldungen, Analysen.

scry

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