Cisco IOS 8.2/8.3/9.0/9.1 Access List privileges management

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability classified as critical has been found in Cisco IOS 8.2/8.3/9.0/9.1 (Router Operating System). This affects an unknown part of the component Access List Handler. The manipulation with an unknown input leads to a privilege escalation vulnerability. CWE is classifying the issue as CWE-269. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was presented 12/10/1992 as CSCdi34061 as confirmed advisory (Website). The advisory is shared at This vulnerability is uniquely identified as CVE-1999-1466. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 10973 (Cisco IOS established Keyword ACL Bypass (CSCdi34061)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CISCO.

Upgrading to version 8.3, 9.0 or 9.1 eliminates this vulnerability. It is possible to mitigate the problem by applying the configuration setting no ip route-cache. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at SecurityFocus (BID 53), X-Force (1248), Vulnerability Center (SBV-2058) and Tenable (10973). See 13652 and 14213 for similar entries.





CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍



VulDB Base Score: 🔍
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NVD Base Score: 🔍


Class: Privilege escalation
CWE: CWE-269
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

Price Prediction: 🔍
Current Price Estimation: 🔍


Nessus ID: 10973
Nessus Name: Cisco IOS established Keyword ACL Bypass (CSCdi34061)
Nessus Family: 🔍

Threat Intelligenceinfoedit

Threat: 🔍
Adversaries: 🔍
Geopolitics: 🔍
Economy: 🔍
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Remediation: 🔍


Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: IOS 8.3/9.0/9.1
Config: no ip route-cache


12/10/1992 🔍
12/10/1992 +0 days 🔍
12/10/1992 +0 days 🔍
12/10/1992 +0 days 🔍
09/01/1998 +2091 days 🔍
09/09/2003 +1834 days 🔍
06/17/2014 +3934 days 🔍
04/10/2015 +297 days 🔍
01/13/2018 +1009 days 🔍



Advisory: CSCdi34061
Status: Confirmed

CVE: CVE-1999-1466 (🔍)
SecurityFocus: 53 - Cisco Access List Vulnerability
X-Force: 1248 - Cisco IOS access control list using the \
Vulnerability Center: 2058 - [cisco-sa-19950601-key-packet-bypass] Cisco IOS established Keyword Allows Filtering Bypass, Low

See also: 🔍


Created: 06/17/2014 12:34 PM
Updated: 01/13/2018 12:44 PM
Changes: (6) vulnerability_cvss2_nvd_av vulnerability_cvss2_nvd_ac vulnerability_cvss2_nvd_au vulnerability_cvss2_nvd_ci vulnerability_cvss2_nvd_ii vulnerability_cvss2_nvd_ai
Complete: 🔍


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