A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) protocol of...

7.4 CVSS

Vulnerability Description

A vulnerability in the Intermediate System-to-Intermediate System (IS-IS) protocol of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient input validation when parsing an ingress IS-IS packet. An attacker could exploit this vulnerability by sending a crafted IS-IS packet to an affected device after forming an adjacency. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: The IS-IS protocol is a routing protocol. To exploit this vulnerability, an attacker must be Layer 2-adjacent to the affected device and have formed an adjacency.

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-isis-sGjyOUHX

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Affected Vendor

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Affected Software

IOS, Cisco IOS XE Software

Vulnerable Versions:

15.2(1)S, 15.2(2)S, 15.2(1)S1, 15.2(4)S, 15.2(1)S2, 15.2(2)S1, 15.2(2)S2, 15.2(2)S0a, 15.2(2)S0c, 15.2(4)S1, 15.2(4)S4, 15.2(4)S6, 15.2(4)S2, 15.2(4)S5, 15.2(4)S3, 15.2(4)S3a, 15.2(4)S4a, 15.2(4)S7, 15.3(1)T, 15.3(2)T, 15.3(1)T1, 15.3(1)T2, 15.3(1)T3, 15.3(1)T4, 15.3(2)T1, 15.3(2)T2, 15.3(2)T3, 15.3(2)T4, 15.1(2)SG, 15.1(2)SG1, 15.1(2)SG2, 15.1(2)SG3, 15.1(2)SG4, 15.1(2)SG5, 15.1(2)SG6, 15.1(2)SG7, 15.1(2)SG8, 15.2(4)M, 15.2(4)M1, 15.2(4)M2, 15.2(4)M4, 15.2(4)M3, 15.2(4)M5, 15.2(4)M8, 15.2(4)M10, 15.2(4)M7, 15.2(4)M6, 15.2(4)M9, 15.2(4)M6a, 15.2(4)M11, 15.0(1)EX, 15.2(3)GC, 15.2(3)GC1, 15.2(4)GC, 15.2(4)GC1, 15.2(4)GC2, 15.2(4)GC3, 15.1(1)SY, 15.1(1)SY1, 15.1(2)SY, 15.1(2)SY1, 15.1(2)SY2, 15.1(1)SY2, 15.1(1)SY3, 15.1(2)SY3, 15.1(1)SY4, 15.1(2)SY4, 15.1(1)SY5, 15.1(2)SY5, 15.1(2)SY4a, 15.1(1)SY6, 15.1(2)SY6, 15.1(2)SY7, 15.1(2)SY8, 15.1(2)SY9, 15.1(2)SY10, 15.1(2)SY11, 15.1(2)SY12, 15.1(2)SY13, 15.1(2)SY14, 15.1(2)SY15, 15.1(2)SY16, 15.3(1)S, 15.3(2)S, 15.3(3)S, 15.3(1)S2, 15.3(1)S1, 15.3(2)S2, 15.3(2)S1, 15.3(3)S1, 15.3(3)S2, 15.3(3)S3, 15.3(3)S6, 15.3(3)S4, 15.3(3)S1a, 15.3(3)S5, 15.3(3)S7, 15.3(3)S8, 15.3(3)S9, 15.3(3)S10, 15.3(3)S8a, 15.4(1)T, 15.4(2)T, 15.4(1)T2, 15.4(1)T1, 15.4(1)T3, 15.4(2)T1, 15.4(2)T3, 15.4(2)T2, 15.4(1)T4, 15.4(2)T4, 15.2(1)E, 15.2(2)E, 15.2(1)E1, 15.2(3)E, 15.2(1)E2, 15.2(1)E3, 15.2(2)E1, 15.2(4)E, 15.2(3)E1, 15.2(2)E2, 15.2(2)E3, 15.2(2a)E2, 15.2(3)E2, 15.2(3a)E, 15.2(3)E3, 15.2(4)E1, 15.2(2)E4, 15.2(2)E5, 15.2(4)E2, 15.2(3)E4, 15.2(5)E, 15.2(4)E3, 15.2(2)E6, 15.2(5)E1, 15.2(2)E5a, 15.2(3)E5, 15.2(2)E5b, 15.2(5a)E1, 15.2(4)E4, 15.2(2)E7, 15.2(5)E2, 15.2(6)E, 15.2(5)E2b, 15.2(4)E5, 15.2(5)E2c, 15.2(2)E8, 15.2(6)E0a, 15.2(6)E1, 15.2(2)E7b, 15.2(4)E5a, 15.2(6)E0c, 15.2(4)E6, 15.2(6)E2, 15.2(2)E9, 15.2(4)E7, 15.2(7)E, 15.2(2)E10, 15.2(4)E8, 15.2(6)E2a, 15.2(7)E1, 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(4)E10a, 15.2(7)E4, 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(4)E10e, 15.2(7)E9, 15.2(8)E5, 15.4(1)S, 15.4(2)S, 15.4(3)S, 15.4(1)S1, 15.4(1)S2, 15.4(2)S1, 15.4(1)S3, 15.4(3)S1, 15.4(2)S2, 15.4(3)S2, 15.4(3)S3, 15.4(1)S4, 15.4(2)S3, 15.4(2)S4, 15.4(3)S4, 15.4(3)S5, 15.4(3)S6, 15.4(3)S7, 15.4(3)S6a, 15.4(3)S8, 15.4(3)S9, 15.4(3)S10, 15.3(3)M, 15.3(3)M1, 15.3(3)M2, 15.3(3)M3, 15.3(3)M5, 15.3(3)M4, 15.3(3)M6, 15.3(3)M7, 15.3(3)M8, 15.3(3)M9, 15.3(3)M10, 15.3(3)M8a, 15.2(1)EY, 15.2(1)SY, 15.2(1)SY1, 15.2(1)SY0a, 15.2(1)SY2, 15.2(2)SY, 15.2(1)SY1a, 15.2(2)SY1, 15.2(2)SY2, 15.2(1)SY3, 15.2(1)SY4, 15.2(2)SY3, 15.2(1)SY5, 15.2(1)SY6, 15.2(1)SY7, 15.2(1)SY8, 15.4(1)CG, 15.4(1)CG1, 15.4(2)CG, 15.5(1)S, 15.5(2)S, 15.5(1)S1, 15.5(3)S, 15.5(1)S2, 15.5(1)S3, 15.5(2)S1, 15.5(2)S2, 15.5(3)S1, 15.5(3)S1a, 15.5(2)S3, 15.5(3)S2, 15.5(3)S0a, 15.5(3)S3, 15.5(1)S4, 15.5(2)S4, 15.5(3)S4, 15.5(3)S5, 15.5(3)S6, 15.5(3)S6a, 15.5(3)S7, 15.5(3)S6b, 15.5(3)S8, 15.5(3)S9, 15.5(3)S10, 15.5(3)S9a, 15.2(2)EB, 15.2(2)EB1, 15.2(2)EB2, 15.2(6)EB, 15.5(1)T, 15.5(1)T1, 15.5(2)T, 15.5(1)T2, 15.5(1)T3, 15.5(2)T1, 15.5(2)T2, 15.5(2)T3, 15.5(2)T4, 15.5(1)T4, 15.2(2)EA, 15.2(2)EA1, 15.2(2)EA2, 15.2(3)EA, 15.2(4)EA, 15.2(4)EA1, 15.2(2)EA3, 15.2(4)EA3, 15.2(5)EA, 15.2(4)EA4, 15.2(4)EA5, 15.2(4)EA6, 15.2(4)EA7, 15.2(4)EA8, 15.2(4)EA9, 15.2(4)EA9a, 15.5(3)M, 15.5(3)M1, 15.5(3)M0a, 15.5(3)M2, 15.5(3)M3, 15.5(3)M4, 15.5(3)M4a, 15.5(3)M5, 15.5(3)M6, 15.5(3)M7, 15.5(3)M6a, 15.5(3)M8, 15.5(3)M9, 15.5(3)M10, 15.5(3)SN, 15.6(1)S, 15.6(2)S, 15.6(2)S1, 15.6(1)S1, 15.6(1)S2, 15.6(2)S2, 15.6(1)S3, 15.6(2)S3, 15.6(1)S4, 15.6(2)S4, 15.6(1)T, 15.6(2)T, 15.6(1)T0a, 15.6(1)T1, 15.6(2)T1, 15.6(1)T2, 15.6(2)T2, 15.6(1)T3, 15.6(2)T3, 15.3(1)SY, 15.3(1)SY1, 15.3(1)SY2, 15.6(2)SP, 15.6(2)SP1, 15.6(2)SP2, 15.6(2)SP3, 15.6(2)SP4, 15.6(2)SP5, 15.6(2)SP6, 15.6(2)SP7, 15.6(2)SP8, 15.6(2)SP9, 15.6(2)SP10, 15.6(2)SN, 15.6(3)M, 15.6(3)M1, 15.6(3)M0a, 15.6(3)M1b, 15.6(3)M2, 15.6(3)M3, 15.6(3)M3a, 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, 15.2(4)EC1, 15.2(4)EC2, 15.4(1)SY, 15.4(1)SY1, 15.4(1)SY2, 15.4(1)SY3, 15.4(1)SY4, 15.5(1)SY, 15.5(1)SY1, 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, 15.7(3)M, 15.7(3)M1, 15.7(3)M0a, 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)M8b, 3.7.0S, 3.7.1S, 3.7.2S, 3.7.3S, 3.7.4S, 3.7.5S, 3.7.6S, 3.7.7S, 3.7.4aS, 3.7.2tS, 3.7.0bS, 3.7.1aS, 3.8.0S, 3.8.1S, 3.8.2S, 3.9.1S, 3.9.0S, 3.9.2S, 3.9.1aS, 3.9.0aS, 3.2.0SE, 3.2.1SE, 3.2.2SE, 3.2.3SE, 3.3.0SE, 3.3.1SE, 3.3.2SE, 3.3.3SE, 3.3.4SE, 3.3.5SE, 3.3.0XO, 3.3.1XO, 3.3.2XO, 3.4.0SG, 3.4.2SG, 3.4.1SG, 3.4.3SG, 3.4.4SG, 3.4.5SG, 3.4.6SG, 3.4.7SG, 3.4.8SG, 3.5.0E, 3.5.1E, 3.5.2E, 3.5.3E, 3.10.0S, 3.10.1S, 3.10.2S, 3.10.3S, 3.10.4S, 3.10.5S, 3.10.6S, 3.10.2tS, 3.10.7S, 3.10.1xbS, 3.10.8S, 3.10.8aS, 3.10.9S, 3.10.10S, 3.11.1S, 3.11.2S, 3.11.0S, 3.11.3S, 3.11.4S, 3.12.0S, 3.12.1S, 3.12.2S, 3.12.3S, 3.12.0aS, 3.12.4S, 3.13.0S, 3.13.1S, 3.13.2S, 3.13.3S, 3.13.4S, 3.13.5S, 3.13.2aS, 3.13.0aS, 3.13.5aS, 3.13.6S, 3.13.7S, 3.13.6aS, 3.13.7aS, 3.13.8S, 3.13.9S, 3.13.10S, 3.6.0E, 3.6.1E, 3.6.2aE, 3.6.2E, 3.6.3E, 3.6.4E, 3.6.5E, 3.6.6E, 3.6.5aE, 3.6.5bE, 3.6.7E, 3.6.8E, 3.6.7bE, 3.6.9E, 3.6.10E, 3.14.0S, 3.14.1S, 3.14.2S, 3.14.3S, 3.14.4S, 3.15.0S, 3.15.1S, 3.15.2S, 3.15.1cS, 3.15.3S, 3.15.4S, 3.7.0E, 3.7.1E, 3.7.2E, 3.7.3E, 3.7.4E, 3.7.5E, 3.16.0S, 3.16.1S, 3.16.1aS, 3.16.2S, 3.16.2aS, 3.16.0cS, 3.16.3S, 3.16.2bS, 3.16.3aS, 3.16.4S, 3.16.4aS, 3.16.4bS, 3.16.5S, 3.16.4dS, 3.16.6S, 3.16.7S, 3.16.6bS, 3.16.7aS, 3.16.7bS, 3.16.8S, 3.16.9S, 3.16.10S, 3.17.0S, 3.17.1S, 3.17.2S, 3.17.1aS, 3.17.3S, 3.17.4S, 16.1.1, 16.1.2, 16.1.3, 16.2.1, 16.2.2, 3.8.0E, 3.8.1E, 3.8.2E, 3.8.3E, 3.8.4E, 3.8.5E, 3.8.5aE, 3.8.6E, 3.8.7E, 3.8.8E, 3.8.9E, 3.8.10E, 3.8.10eE, 16.3.1, 16.3.2, 16.3.3, 16.3.1a, 16.3.4, 16.3.5, 16.3.5b, 16.3.6, 16.3.7, 16.3.8, 16.3.9, 16.3.10, 16.3.11, 16.4.1, 16.4.2, 16.4.3, 16.5.1, 16.5.1a, 16.5.1b, 16.5.2, 16.5.3, 3.18.0aS, 3.18.0S, 3.18.1S, 3.18.2S, 3.18.3S, 3.18.4S, 3.18.0SP, 3.18.1SP, 3.18.1aSP, 3.18.1bSP, 3.18.1cSP, 3.18.2SP, 3.18.2aSP, 3.18.3SP, 3.18.4SP, 3.18.3aSP, 3.18.3bSP, 3.18.5SP, 3.18.6SP, 3.18.7SP, 3.18.8aSP, 3.18.9SP, 3.9.0E, 3.9.1E, 3.9.2E, 16.6.1, 16.6.2, 16.6.3, 16.6.4, 16.6.5, 16.6.4a, 16.6.5a, 16.6.6, 16.6.7, 16.6.8, 16.6.9, 16.6.10, 16.7.1, 16.7.1a, 16.7.1b, 16.7.2, 16.7.3, 16.7.4, 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, 3.10.0E, 3.10.1E, 3.10.0cE, 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, 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, 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, 17.6.5a, 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, 17.9.1y1, 17.11.1, 17.11.1a, 17.11.99SW