Cisco IOS XE up to 17.16.1a CLI User parameter delimiter

CVSS Meta Temp Score
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CTI Interest Score
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6.4$0-$5k0.57

Summaryinfo

A vulnerability identified as critical has been detected in Cisco IOS XE. The impacted element is an unknown function of the component CLI. Performing a manipulation of the argument User results in parameter delimiter. This vulnerability is identified as CVE-2025-20338. The attack is only possible with local access. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Cisco IOS XE. It has been classified as critical. This affects some unknown functionality of the component CLI. The manipulation of the argument user with an unknown input leads to a parameter delimiter vulnerability. CWE is classifying the issue as CWE-141. The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as parameter or argument delimiters when they are sent to a downstream component. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

A vulnerability in the CLI of Cisco IOS XE Software could allow an authenticated, local attacker with administrative privileges to execute arbitrary commands as root on the underlying operating system of an affected device. This vulnerability is due to insufficient validation of user arguments that are passed to specific CLI commands. An attacker could exploit this vulnerability by logging in to the device CLI with valid administrative (level 15) credentials and using crafted commands at the CLI prompt. A successful exploit could allow the attacker to execute arbitrary commands as root.

The advisory is shared at sec.cloudapps.cisco.com. This vulnerability is uniquely identified as CVE-2025-20338 since 10/10/2024. The exploitability is told to be easy. An attack has to be approached locally. The exploitation needs additional levels of successful authentication. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/15/2025).

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-31025). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.4

VulDB Base Score: 6.7
VulDB Temp Score: 6.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.7
NVD Vector: 🔒

CNA Base Score: 6.0
CNA Vector (cisco): 🔒

CVSSv2info

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

Exploitinginfo

Class: Parameter delimiter
CWE: CWE-141 / CWE-140 / CWE-20
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

10/10/2024 CVE reserved
09/24/2025 +349 days Advisory disclosed
09/24/2025 +0 days VulDB entry created
11/15/2025 +52 days VulDB entry last update

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-iosxe-arg-inject-EyDDbh4e
Status: Confirmed

CVE: CVE-2025-20338 (🔒)
GCVE (CVE): GCVE-0-2025-20338
GCVE (VulDB): GCVE-100-325761
EUVD: 🔒
scip Labs: https://www.scip.ch/en/?labs.20150108

Entryinfo

Created: 09/24/2025 19:28
Updated: 11/15/2025 08:13
Changes: 09/24/2025 19:28 (66), 09/25/2025 08:29 (1), 11/15/2025 08:13 (12)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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