Cisco NX-OS/Wireless LAN Controller Integrated Security Feature buffer access with incorrect length value

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.8$5k-$25k0.00

Summaryinfo

A vulnerability classified as critical was found in Cisco NX-OS and Wireless LAN Controller. Affected by this issue is some unknown functionality of the component Integrated Security Feature. The manipulation results in buffer access with incorrect length value. This vulnerability is reported as CVE-2025-20191. The attacker must have access to the local network to execute the attack. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, was found in Cisco NX-OS and Wireless LAN Controller (version unknown). Affected is an unknown function of the component Integrated Security Feature. The manipulation with an unknown input leads to a buffer access with incorrect length value vulnerability. CWE is classifying the issue as CWE-805. The product uses a sequential operation to read or write a buffer, but it uses an incorrect length value that causes it to access memory that is outside of the bounds of the buffer. This is going to have an impact on availability. CVE summarizes:

A vulnerability in the Switch Integrated Security Features (SISF) of Cisco IOS Software, Cisco IOS XE Software, Cisco NX-OS Software, and Cisco Wireless LAN Controller (WLC) AireOS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to the incorrect handling of DHCPv6 packets. An attacker could exploit this vulnerability by sending a crafted DHCPv6 packet to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

The advisory is available at sec.cloudapps.cisco.com. This vulnerability is traded as CVE-2025-20191 since 10/10/2024. The exploitability is told to be easy. The attack needs to approached within the local network. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 05/08/2025).

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: 6.9
VulDB Meta Temp Score: 6.8

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 7.4
CNA Vector (cisco): 🔍

CVSSv2info

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

Exploitinginfo

Class: Buffer access with incorrect length value
CWE: CWE-805 / CWE-120 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Partially

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 🔍
05/07/2025 +209 days 🔍
05/07/2025 +0 days 🔍
05/08/2025 +1 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-sisf-dos-ZGwt4DdY
Status: Confirmed

CVE: CVE-2025-20191 (🔍)
GCVE (CVE): GCVE-0-2025-20191
GCVE (VulDB): GCVE-100-307902

Entryinfo

Created: 05/07/2025 20:12
Updated: 05/08/2025 10:53
Changes: 05/07/2025 20:12 (63), 05/08/2025 10:53 (1)
Complete: 🔍
Cache ID: 216::103

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Discussion

 Anonymous User (+0)
1 Year ago
Good morning, I couldn’t find this CPE in the NVD NIST CPE Dictionary. Instead, I see `cisco:nx-os`. Could you kindly verify this? Thanks a lot.
 VulDB Community Team1 Year ago
Thank you, we have just aligned the CPE.

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