CVE-2024-20312

highpriority · track · 0EPSS 0.003 · 17 %ileDEEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.26% (17th) EPSS
CVSS 7.4 · high
Is it mine?
2,599 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · cert_bund · cisco_csaf

EPSS · scored 2026-10-27

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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

7.4
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.8–7.4

v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · ENISA EU
v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · psirt@cisco.com USexploitability 2.8 · impact 4
v3.16.8mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.17.4highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · Cisco PSIRT US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

05

affected products (2,599)

Products and version ranges known to be affected.

06

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2024-0740Cisco IOS: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2024-03-27csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Cisco IOS und Cisco IOS XE ausnutzen, um einen Denial of Service Angriff durchzuführen.

  • cisco-sa-isis-sGjyOUHXCisco IOS and IOS XE Software Intermediate System-to-Intermediate System Denial of Service Vulnerability2024-03-27csaf · cisco_csafUS

    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. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is part of the March 2024 release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: March 2024 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75056"].

07

also known as (3)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

published 2024-03-27modified 2026-06-17
09

references (5)

External citations — patches, advisories, analysis.

scry

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