Cisco IOS Software and Cisco IOS XE Software Quality of Service Remote Code Execution Vulnerability
- Severity
- Critical9.8CVSS 3.1, Critical
- EPSS
- 14%
- Published
- 28 Mar 2018
- Updated
- 17 Jun 2026
Description
Title, description and vendor guidance are quoted from the source records.
A vulnerability in the quality of service (QoS) subsystem of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges. The vulnerability is due to incorrect bounds checking of certain values in packets that are destined for UDP port 18999 of an affected device. An attacker could exploit this vulnerability by sending malicious packets to an affected device. When the packets are processed, an exploitable buffer overflow condition may occur. A successful exploit could allow the attacker to execute arbitrary code on the affected device with elevated privileges. The attacker could also leverage this vulnerability to cause the device to reload, causing a temporary DoS condition while the device is reloading. The malicious packets must be destined to and processed by an affected device. Traffic transiting a device will not trigger the vulnerability. Cisco Bug IDs: CSCvf73881.
Weakness: CWE-119
Known exploited
Added to CISA KEV on 3 Mar 2022
Federal remediation due date: 17 Mar 2022
Required action: Apply updates per vendor instructions.
Exploit prediction
14% probability of exploitation in the next 30 days (percentile 96%).
CVSS:3.1/AV:N/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.
- n/a Cisco IOS and IOS XE · Cisco IOS and IOS XE
References
Provenance
Every fact on this page comes from the sources below. Nothing is written by an AI.
- Cisco (CVE record)
- Cisco (CVE record) · 27 Sept 2026, 23:46 UTC · Parser patcharo-cve5/1.1.0
- CISA Known Exploited Vulnerabilities
- CISA Known Exploited Vulnerabilities · 27 Sept 2026, 23:42 UTC · Parser patcharo-kev/1.0.0
- NVD
- NVD · 27 Sept 2026, 23:44 UTC · Parser patcharo-nvd/1.0.0
- FIRST EPSS
- FIRST EPSS · 27 Sept 2026, 23:46 UTC · Parser patcharo-epss/1.0.0
Last verified: 28 Sept 2026, 02:31 UTC