CVE-2021-1622
CVE-2021-1622 is a high-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 8.6. 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-667.
Key facts
- Severity: High (CVSS 3.x base score 8.6)
- CVSS v2: 4.3
- EPSS exploit prediction: 1% (57th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-667
- Affected product: Cisco Ios Xe
- Published:
- Last modified:
Description
A vulnerability in the Common Open Policy Service (COPS) of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, remote attacker to cause resource exhaustion, resulting in a denial of service (DoS) condition. This vulnerability is due to a deadlock condition in the code when processing COPS packets under certain conditions. An attacker could exploit this vulnerability by sending COPS packets with high burst rates to an affected device. A successful exploit could allow the attacker to cause the CPU to consume excessive resources, which prevents other control plane processes from obtaining resources and results in a DoS.
Frequently asked questions
- What is CVE-2021-1622?
- A vulnerability in the Common Open Policy Service (COPS) of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, remote attacker to cause resource exhaustion, resulting in a denial of service (DoS) condition. This vulnerability is due to a deadlock condition in the code when processing COPS packets under certain conditions. An attacker could exploit this vulnerability by sending COPS packets with high burst rates to an affected device. A successful exploit could allow the attacker to cause the CPU to consume excessive resources, which prevents other control plane processes from obtaining resources and results in a DoS.
- How severe is CVE-2021-1622?
- CVE-2021-1622 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-1622 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-1622?
- CVE-2021-1622 primarily affects Cisco Ios Xe. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-1622?
- 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-2021-1622 published?
- CVE-2021-1622 was published on 2021-09-23 and last updated on 2026-06-17.
References
Affected products (2)
- cpe:2.3:o:cisco:ios_xe:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.3.1x:*:*:*:*:*:*:*
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