A vulnerability in the implementation of the TACACS+ protocol in...

8.1 CVSS

Vulnerability Description

A vulnerability in the implementation of the TACACS+ protocol in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to view sensitive data or bypass authentication. This vulnerability exists because the system does not properly check whether the required TACACS+ shared secret is configured. A machine-in-the-middle attacker could exploit this vulnerability by intercepting and reading unencrypted TACACS+ messages or impersonating the TACACS+ server and falsely accepting arbitrary authentication requests. A successful exploit could allow the attacker to view sensitive information in a TACACS+ message or bypass authentication and gain access to the affected device.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-tacacs-hdB7thJw

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Affected Vendor

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Affected Software

IOS, Cisco IOS XE Software

Vulnerable Versions:

15.2(6)E1, 15.2(4)E6, 15.2(6)E2, 15.2(4)E7, 15.2(7)E, 15.2(4)E8, 15.2(6)E2a, 15.2(6)E2b, 15.2(7)E1, 15.2(7)E0a, 15.2(7)E0b, 15.2(7)E0s, 15.2(6)E3, 15.2(4)E9, 15.2(7)E2, 15.2(7a)E0b, 15.2(4)E10, 15.2(7)E3, 15.2(7)E1a, 15.2(7b)E0b, 15.2(7)E2a, 15.2(4)E10a, 15.2(7)E4, 15.2(7)E3k, 15.2(8)E, 15.2(8)E1, 15.2(7)E5, 15.2(7)E6, 15.2(8)E2, 15.2(4)E10d, 15.2(7)E7, 15.2(8)E3, 15.2(7)E8, 15.2(8)E4, 15.2(7)E9, 15.2(8)E5, 15.2(8)E6, 15.2(7)E10, 15.2(7)E11, 15.2(8)E7, 15.2(7)E12, 15.5(3)S8, 15.5(3)S9, 15.5(3)S10, 15.5(3)S9a, 15.2(6)EB, 15.5(3)M7, 15.5(3)M8, 15.5(3)M9, 15.5(3)M10, 15.6(2)SP5, 15.6(2)SP6, 15.6(2)SP7, 15.6(2)SP8, 15.6(2)SP9, 15.6(3)M4, 15.6(3)M5, 15.6(3)M6, 15.6(3)M7, 15.6(3)M6a, 15.6(3)M6b, 15.6(3)M8, 15.6(3)M9, 15.5(1)SY2, 15.5(1)SY3, 15.5(1)SY4, 15.5(1)SY5, 15.5(1)SY6, 15.5(1)SY7, 15.5(1)SY8, 15.5(1)SY9, 15.5(1)SY10, 15.5(1)SY11, 15.5(1)SY12, 15.5(1)SY13, 15.5(1)SY14, 15.5(1)SY15, 15.7(3)M3, 15.7(3)M2, 15.7(3)M4, 15.7(3)M5, 15.7(3)M4a, 15.7(3)M4b, 15.7(3)M6, 15.7(3)M7, 15.7(3)M8, 15.7(3)M9, 15.8(3)M, 15.8(3)M1, 15.8(3)M0a, 15.8(3)M0b, 15.8(3)M2, 15.8(3)M1a, 15.8(3)M3, 15.8(3)M2a, 15.8(3)M4, 15.8(3)M3a, 15.8(3)M3b, 15.8(3)M5, 15.8(3)M6, 15.8(3)M7, 15.8(3)M8, 15.8(3)M9, 15.9(3)M, 15.9(3)M1, 15.9(3)M0a, 15.9(3)M2, 15.9(3)M3, 15.9(3)M2a, 15.9(3)M3a, 15.9(3)M4, 15.9(3)M3b, 15.9(3)M5, 15.9(3)M4a, 15.9(3)M6, 15.9(3)M7, 15.9(3)M6a, 15.9(3)M6b, 15.9(3)M8, 15.9(3)M7a, 15.9(3)M9, 15.9(3)M8b, 15.9(3)M10, 15.9(3)M11, 3.16.8S, 3.16.9S, 3.16.10S, 3.8.6E, 3.8.7E, 3.8.8E, 3.8.9E, 3.8.10E, 3.18.5SP, 3.18.6SP, 3.18.7SP, 3.18.8aSP, 3.18.9SP, 16.6.5, 16.6.5a, 16.6.6, 16.6.7, 16.6.8, 16.6.9, 16.6.10, 16.8.1, 16.8.1a, 16.8.1b, 16.8.1s, 16.8.1c, 16.8.1d, 16.8.2, 16.8.1e, 16.8.3, 16.9.1, 16.9.2, 16.9.1a, 16.9.1b, 16.9.1s, 16.9.3, 16.9.4, 16.9.3a, 16.9.5, 16.9.5f, 16.9.6, 16.9.7, 16.9.8, 16.10.1, 16.10.1a, 16.10.1b, 16.10.1s, 16.10.1c, 16.10.1e, 16.10.1d, 16.10.2, 16.10.1f, 16.10.1g, 16.10.3, 3.10.1E, 3.10.2E, 3.10.3E, 16.11.1, 16.11.1a, 16.11.1b, 16.11.2, 16.11.1s, 16.12.1, 16.12.1s, 16.12.1a, 16.12.1c, 16.12.1w, 16.12.2, 16.12.1y, 16.12.2a, 16.12.3, 16.12.8, 16.12.2s, 16.12.1x, 16.12.1t, 16.12.4, 16.12.3s, 16.12.3a, 16.12.4a, 16.12.5, 16.12.6, 16.12.1z1, 16.12.5a, 16.12.5b, 16.12.1z2, 16.12.6a, 16.12.7, 16.12.9, 16.12.10, 16.12.10a, 16.12.11, 16.12.12, 16.12.13, 3.11.0E, 3.11.1E, 3.11.2E, 3.11.3E, 3.11.1aE, 3.11.4E, 3.11.3aE, 3.11.5E, 3.11.6E, 3.11.7E, 3.11.8E, 3.11.9E, 3.11.10E, 3.11.11E, 3.11.12E, 17.1.1, 17.1.1a, 17.1.1s, 17.1.1t, 17.1.3, 17.2.1, 17.2.1r, 17.2.1a, 17.2.1v, 17.2.2, 17.2.3, 17.3.1, 17.3.2, 17.3.3, 17.3.1a, 17.3.1w, 17.3.2a, 17.3.1x, 17.3.1z, 17.3.4, 17.3.5, 17.3.4a, 17.3.6, 17.3.4b, 17.3.4c, 17.3.5a, 17.3.5b, 17.3.7, 17.3.8, 17.3.8a, 17.4.1, 17.4.2, 17.4.1a, 17.4.1b, 17.4.2a, 17.5.1, 17.5.1a, 17.6.1, 17.6.2, 17.6.1w, 17.6.1a, 17.6.1x, 17.6.3, 17.6.1y, 17.6.1z, 17.6.3a, 17.6.4, 17.6.1z1, 17.6.5, 17.6.6, 17.6.6a, 17.6.5a, 17.6.7, 17.6.8, 17.6.8a, 17.7.1, 17.7.1a, 17.7.1b, 17.7.2, 17.10.1, 17.10.1a, 17.10.1b, 17.8.1, 17.8.1a, 17.9.1, 17.9.1w, 17.9.2, 17.9.1a, 17.9.1x, 17.9.1y, 17.9.3, 17.9.2a, 17.9.1x1, 17.9.3a, 17.9.4, 17.9.1y1, 17.9.5, 17.9.4a, 17.9.5a, 17.9.5b, 17.9.6, 17.9.6a, 17.9.7, 17.9.5e, 17.9.5f, 17.9.7a, 17.9.7b, 17.11.1, 17.11.1a, 17.12.1, 17.12.1w, 17.12.1a, 17.12.1x, 17.12.2, 17.12.3, 17.12.2a, 17.12.1y, 17.12.1z, 17.12.4, 17.12.3a, 17.12.1z1, 17.12.1z2, 17.12.4a, 17.12.5, 17.12.4b, 17.12.1z3, 17.12.5a, 17.12.1z4, 17.12.5b, 17.12.5c, 17.13.1, 17.13.1a, 17.14.1, 17.14.1a, 17.11.99SW, 17.15.1, 17.15.1w, 17.15.1a, 17.15.2, 17.15.1b, 17.15.1x, 17.15.3, 17.15.2c, 17.15.2a, 17.15.1y, 17.15.2b, 17.15.3a, 17.15.3b