CVE-2022-20849

MEDIUM

Published Nov 15, 2024 Modified Aug 1, 2025 CWE-391

Description

A vulnerability in the Broadband Network Gateway PPP over Ethernet (PPPoE) feature of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause the PPPoE process to continually crash. This vulnerability exists because the PPPoE feature does not properly handle an error condition within a specific crafted packet sequence. An attacker could exploit this vulnerability by sending a sequence of specific PPPoE packets from controlled customer premises equipment (CPE). A successful exploit could allow the attacker to cause the PPPoE process to continually restart, resulting in a denial of service condition (DoS).Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.This advisory is part of the September 2022 release of the Cisco IOS XR Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see .

CVSS v3.1 Score

6.1

MEDIUM

CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H

Weakness Type (CWE)

CWE-391 CWE-391

Affected Products

Vendor	Product	Versions
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	ios_xr	All
cisco	asr_9006	All
cisco	asr_9010	All
cisco	asr_9901	All
cisco	asr_9902	All
cisco	asr_9903	All
cisco	asr_9904	All
cisco	asr_9906	All
cisco	asr_9910	All
cisco	asr_9912	All
cisco	asr_9922	All
cisco	ios_xrv_9000	All

References

Advisories & Patches

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-bng-Gmg5Gxt

Frequently Asked Questions

What is CVE-2022-20849? +

How severe is CVE-2022-20849? +

CVE-2022-20849 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2022-20849? +

CVE-2022-20849 affects products from cisco, specifically: asr_9006, asr_9010, asr_9901, asr_9902, asr_9903, asr_9904, asr_9906, asr_9910, asr_9912, asr_9922, ios_xr, ios_xrv_9000. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2022-20849? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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