CVE-2020-3508
CVE-2020-3508 is a high-severity vulnerability in Cisco Ios Xe 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-400.
Key facts
- Severity: High (CVSS 3.x base score 7.4)
- CVSS v2: 6.1
- EPSS exploit prediction: 0% (35th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-400
- Affected product: Cisco Ios Xe
- Published:
- Last modified:
Description
A vulnerability in the IP Address Resolution Protocol (ARP) feature of Cisco IOS XE Software for Cisco ASR 1000 Series Aggregation Services Routers with a 20-Gbps Embedded Services Processor (ESP) installed could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service condition. The vulnerability is due to insufficient error handling when an affected device has reached platform limitations. An attacker could exploit this vulnerability by sending a malicious series of IP ARP messages to an affected device. A successful exploit could allow the attacker to exhaust system resources, which would eventually cause the affected device to reload.
Frequently asked questions
- What is CVE-2020-3508?
- A vulnerability in the IP Address Resolution Protocol (ARP) feature of Cisco IOS XE Software for Cisco ASR 1000 Series Aggregation Services Routers with a 20-Gbps Embedded Services Processor (ESP) installed could allow an unauthenticated, adjacent attacker to cause an affected device to reload, resulting in a denial of service condition. The vulnerability is due to insufficient error handling when an affected device has reached platform limitations. An attacker could exploit this vulnerability by sending a malicious series of IP ARP messages to an affected device. A successful exploit could allow the attacker to exhaust system resources, which would eventually cause the affected device to reload.
- How severe is CVE-2020-3508?
- CVE-2020-3508 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-2020-3508 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-3508?
- CVE-2020-3508 primarily affects Cisco Ios Xe. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-3508?
- 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-2020-3508 published?
- CVE-2020-3508 was published on 2020-09-24 and last updated on 2026-06-17.
References
Affected products (6)
- cpe:2.3:o:cisco:ios_xe:16.3.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.5:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.7\(1\):*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.1.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.4.1:*:*:*:*:*:*:*
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