How severe is CVE-2018-0241?

CVE-2018-0241 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-0241 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-0241?

CVE-2018-0241 primarily affects Cisco Ios Xr. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-0241?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-0241 published?

CVE-2018-0241 was published on 2018-04-19 and last updated on 2026-06-17.

CVE-2018-0241

CVE-2018-0241 is a high-severity vulnerability in Cisco Ios Xr with a CVSS 3.x base score of 7.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-399.

Key facts

Severity: High (CVSS 3.x base score 7.4)
CVSS v2: 6.1
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-399
Affected product: Cisco Ios Xr
Published: 2018-04-19
Last modified: 2026-06-17

Description

A vulnerability in the UDP broadcast forwarding function of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on the affected device. The vulnerability is due to improper handling of UDP broadcast packets that are forwarded to an IPv4 helper address. An attacker could exploit this vulnerability by sending multiple UDP broadcast packets to the affected device. An exploit could allow the attacker to cause a buffer leak on the affected device, eventually resulting in a DoS condition requiring manual intervention to recover. This vulnerability affects all Cisco IOS XR platforms running 6.3.1, 6.2.3, or earlier releases of Cisco IOS XR Software when at least one IPv4 helper address is configured on an interface of the device. Cisco Bug IDs: CSCvi35625.

Frequently asked questions

What is CVE-2018-0241?: A vulnerability in the UDP broadcast forwarding function of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on the affected device. The vulnerability is due to improper handling of UDP broadcast packets that are forwarded to an IPv4 helper address. An attacker could exploit this vulnerability by sending multiple UDP broadcast packets to the affected device. An exploit could allow the attacker to cause a buffer leak on the affected device, eventually resulting in a DoS condition requiring manual intervention to recover. This vulnerability affects all Cisco IOS XR platforms running 6.3.1, 6.2.3, or earlier releases of Cisco IOS XR Software when at least one IPv4 helper address is configured on an interface of the device. Cisco Bug IDs: CSCvi35625.
How severe is CVE-2018-0241?: CVE-2018-0241 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-0241 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-0241?: CVE-2018-0241 primarily affects Cisco Ios Xr. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-0241?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-0241 published?: CVE-2018-0241 was published on 2018-04-19 and last updated on 2026-06-17.

References

Affected products (13)

cpe:2.3:o:cisco:ios_xr:4.0.4.base:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:4.1.3.base:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:4.2.4.base:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:4.3.4.base:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:4.4.3.ce:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:5.0.3.ce:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:5.1.4.base:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:5.2.5.ce:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:5.3.4.base:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:5.4.3.ce:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.0.4.base:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.1.4.base:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xr:6.2.3.base:*:*:*:*:*:*:*

More vulnerabilities in Cisco Ios Xr

CVE-2020-3284 — Critical (CVSS 9.8): A vulnerability in the enhanced Preboot eXecution Environment (PXE) boot loader for Cisco IOS XR 64-bit Software could…
CVE-2019-1710 — Critical (CVSS 9.8): A vulnerability in the sysadmin virtual machine (VM) on Cisco ASR 9000 Series Aggregation Services Routers running…
CVE-2025-20363 — Critical (CVSS 9.0): A vulnerability in the web services of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, Cisco Secure…
CVE-2026-20046 — High (CVSS 8.8): A vulnerability in task group assignment for a specific CLI command in Cisco IOS XR Software could allow an…
CVE-2026-20040 — High (CVSS 8.8): A vulnerability in the CLI of Cisco IOS XR Software could allow an authenticated, local attacker to execute arbitrary…
CVE-2025-20138 — High (CVSS 8.8): A vulnerability in the CLI of Cisco IOS XR Software could allow an authenticated, local attacker to execute arbitrary…

All CVEs affecting Cisco Ios Xr →

Other CWE-399 (Resource Management Errors) vulnerabilities

CVE-2015-8104 — Critical (CVSS 10.0): The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows guest OS users to cause a…
CVE-2015-0339 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0335 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2015-0333 — Critical (CVSS 10.0): Adobe Flash Player before 13.0.0.277 and 14.x through 17.x before 17.0.0.134 on Windows and OS X and before…
CVE-2014-4121 — Critical (CVSS 10.0): Microsoft .NET Framework 2.0 SP2, 3.5, 3.5.1, 4, 4.5, 4.5.1, and 4.5.2 does not properly parse internationalized…
CVE-2014-0560 — Critical (CVSS 10.0): Use-after-free vulnerability in Adobe Reader and Acrobat 10.x before 10.1.12 and 11.x before 11.0.09 on Windows and OS…

Browse all CWE-399 (Resource Management Errors) vulnerabilities →