Cisco ThousandEyes Enterprise Agent up to 5.1.2 CLI link following

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Cisco ThousandEyes Enterprise Agent up to 5.1.2. This affects an unknown part of the component CLI. The manipulation leads to link following. This vulnerability is referenced as CVE-2026-20161. The attack can only be performed from a local environment. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Cisco ThousandEyes Enterprise Agent up to 5.1.2 and classified as critical. This issue affects some unknown processing of the component CLI. The manipulation with an unknown input leads to a link following vulnerability. Using CWE to declare the problem leads to CWE-59. The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A vulnerability in the CLI of Cisco ThousandEyes Enterprise Agent could allow an authenticated, local attacker with low privileges to overwrite arbitrary files on the local system of an affected device. This vulnerability is due to improper access controls on files that are on the local file system of an affected device. An attacker could exploit this vulnerability by placing a symbolic link in a specific location on the local file system. A successful exploit could allow the attacker to bypass file system permissions and overwrite arbitrary files on the affected device.

It is possible to read the advisory at sec.cloudapps.cisco.com. The identification of this vulnerability is CVE-2026-20161 since 10/08/2025. The exploitation is known to be easy. Attacking locally is a requirement. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/16/2026).

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-22965). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.5
CNA Vector (cisco): 🔒

CVSSv2info

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

Exploitinginfo

Class: Link following
CWE: CWE-59
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

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

10/08/2025 CVE reserved
04/15/2026 +189 days Advisory disclosed
04/15/2026 +0 days VulDB entry created
04/16/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-te-agentfilewrite-tqUw3SMU
Status: Confirmed

CVE: CVE-2026-20161 (🔒)
GCVE (CVE): GCVE-0-2026-20161
GCVE (VulDB): GCVE-100-357755
EUVD: 🔒

Entryinfo

Created: 04/15/2026 18:31
Updated: 04/16/2026 01:07
Changes: 04/15/2026 18:31 (64), 04/16/2026 01:07 (1)
Complete: 🔍
Cache ID: 216::103

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