Cisco IOS XR Software Cisco Discovery Protocol Format String Vulnerability
- Severity
- High8.8CVSS 3.1, High
- Known exploited
- Known exploitedFederal remediation due date: 3 May 2022
- Exploit prediction
- 12%
- Published
- 5 Feb 2020Updated 17 Jun 2026 · Last verified 29 Sept 2026
Description
Title, description and vendor guidance are quoted from the source records.
A vulnerability in the Cisco Discovery Protocol implementation for Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to execute arbitrary code or cause a reload on an affected device. The vulnerability is due to improper validation of string input from certain fields in Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to cause a stack overflow, which could allow the attacker to execute arbitrary code with administrative privileges on an affected device. Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).
Weakness: CWE-134, CWE-787
Known exploited
Added to CISA KEV on 3 Nov 2021
Federal remediation due date: 3 May 2022
Required action: Apply updates per vendor instructions.
Exploit prediction
12% probability of exploitation in the next 30 days (percentile 96%).
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Patcharo shows this vulnerability for information but does not match versions for this product yet.
- Cisco Cisco IOS XR Software · unspecified < 6.6.3
References
Provenance
Every fact on this page comes from the sources below. Nothing is written by an AI.
- Cisco (CVE record)
- Cisco (CVE record) · 29 Sept 2026 at 12:17 UTC · Parser patcharo-cve5/1.1.0
- CISA Known Exploited Vulnerabilities
- CISA Known Exploited Vulnerabilities · 29 Sept 2026 at 12:17 UTC · Parser patcharo-kev/1.0.0
- NVD
- NVD · 27 Sept 2026 at 23:44 UTC · Parser patcharo-nvd/1.0.0
- FIRST EPSS
- FIRST EPSS · 30 Sept 2026 at 00:17 UTC · Parser patcharo-epss/1.0.0
Last verified: 29 Sept 2026 at 12:17 UTC