Cisco IOS XE CAPWAP Packet heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.7$5k-$25k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Cisco IOS XE. This affects an unknown part of the component CAPWAP Packet Handler. This manipulation causes heap-based overflow. The identification of this vulnerability is CVE-2021-34770. It is possible to initiate the attack remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Cisco IOS XE (Router Operating System) (the affected version is unknown). It has been declared as very critical. Affected by this vulnerability is an unknown code of the component CAPWAP Packet Handler. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was shared 09/23/2021 as cisco-sa-ewlc-capwap-rce-LYgj8Kf. The advisory is shared at tools.cisco.com. This vulnerability is known as CVE-2021-34770 since 06/15/2021. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 10/30/2025).

Upgrading eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.7

VulDB Base Score: 9.8
VulDB Temp Score: 9.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CNA Base Score: 10.0
CNA Vector (Cisco Systems, Inc.): 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

06/15/2021 🔍
09/23/2021 +100 days 🔍
09/23/2021 +0 days 🔍
10/30/2025 +1498 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-ewlc-capwap-rce-LYgj8Kf
Status: Confirmed

CVE: CVE-2021-34770 (🔍)
GCVE (CVE): GCVE-0-2021-34770
GCVE (VulDB): GCVE-100-183229
scip Labs: https://www.scip.ch/en/?labs.20150108

Entryinfo

Created: 09/23/2021 10:05
Updated: 10/30/2025 22:47
Changes: 09/23/2021 10:05 (49), 10/01/2021 13:11 (1), 10/30/2025 22:47 (31)
Complete: 🔍
Cache ID: 216::103

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