CISA KEV catalog
Confirmed active exploitation.
Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.
- Name
- Cisco IOS Software and Cisco IOS XE Software Quality of Service Remote Code Execution Vulnerability
- Added to catalog
- Remediation due date (US federal)
- Required action
- Apply updates per vendor instructions.
Description
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.
Affected products
cisco: ios xe
References9
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/c… MitigationVendor Advisory
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/c… MitigationVendor Advisory
- www.securityfocus.com/bid/103540 Third Party AdvisoryVDB Entry
- www.securitytracker.com/id/1040582 Third Party AdvisoryVDB Entry
- ics-cert.us-cert.gov/advisories/ICSA-18-107-03 Third Party AdvisoryUS Government Resource
- www.securityfocus.com/bid/103540 Third Party AdvisoryVDB Entry
- www.securitytracker.com/id/1040582 Third Party AdvisoryVDB Entry
- ics-cert.us-cert.gov/advisories/ICSA-18-107-03 Third Party AdvisoryUS Government Resource
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=… US Government Resource
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 14% percentile: 97 · as of 10 November 2026
- CWE
- CWE-119
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