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CISA KEV·Added 2022-03-03 — agencies required to remediate by 2022-03-17

CVE-2018-0151

CRITICAL

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…

Published
Mar 28, 2018
Updated
Jun 17, 2026
Affected
0 pkgs
Patched
None yet
Exploits
2 known

EPSS Exploitation Probability

via FIRST.org ↗
14.5%probability of exploitation in next 30 days
Moderate Risk96th percentile+0.26%
3.27%7.86%12.5%17.1%5.9%14.5%Jan 26May 26Jul 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

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

1 product · 2 configurations
OS
ios xecisco
1 version
16.5.1
Exploits & PoCs
2

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Detection & mitigation playbook

Vendor / appliance
  1. Detect

    Inventory every cisco ios xe deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for remote code execution at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.

  2. Remediation status

    No patch has shipped for CVE-2018-0151 yet — track the cisco ios xe advisory for a fixed release and apply the workarounds below in the meantime.

  3. Mitigate without a patch

    Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.

  4. How O3 protects you

    O3 detects and blocks CVE-2018-0151 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Tailored to CVE-2018-0151. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

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 coul
O3 Security · Runtime Protection

Is CVE-2018-0151 being exploited in your environment?

O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2018-0151 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.