CVE-2021-34770

highpriority · track · 40EPSS 0.030 · 87 %ileEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
2.96% (87th) EPSS
CVSS 9 · high
Is it mine?
58 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, remote attacker to execute arbitrary code with administrative privileges or cause a denial of service (DoS) condition on an affected device. The vulnerability is due to a logic error that occurs during the validation of CAPWAP packets. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device. A successful exploit could allow the attacker to execute arbitrary code with administrative privileges or cause the affected device to crash and reload, resulting in a DoS condition.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

10.0
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 9–10

v2.09highAV:N/AC:L/Au:S/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 8 · impact 10
v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9
v3.110criticalAV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · ENISA EU
v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · psirt@cisco.com USexploitability 3.9 · impact 6
v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · Cisco PSIRT US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

05

affected products (58)

Products and version ranges known to be affected.

06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-ewlc-capwap-rce-LYgj8KfCisco IOS XE Software for Catalyst 9000 Family Wireless Controllers CAPWAP Remote Code Execution Vulnerability2021-09-22csaf · cisco_csafUS

    A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, remote attacker to execute arbitrary code with administrative privileges or cause a denial of service (DoS) condition on an affected device. The vulnerability is due to a logic error that occurs during the validation of CAPWAP packets. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device. A successful exploit could allow the attacker to execute arbitrary code with administrative privileges or cause the affected device to crash and reload, resulting in a DoS condition. 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

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

published 2021-09-23modified 2026-06-17
10

references (8)

External citations — patches, advisories, analysis.

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