CVE-2021-1431
CVE-2021-1431 is a high-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 7.5. 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-20.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 7.8
- EPSS exploit prediction: 2% (73rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Cisco Ios Xe
- Published:
- Last modified:
Description
A vulnerability in the vDaemon process of Cisco IOS XE SD-WAN Software could allow an unauthenticated, remote attacker to cause a device to reload, resulting a denial of service (DoS) condition. This vulnerability is due to insufficient handling of malformed packets. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
Frequently asked questions
- What is CVE-2021-1431?
- A vulnerability in the vDaemon process of Cisco IOS XE SD-WAN Software could allow an unauthenticated, remote attacker to cause a device to reload, resulting a denial of service (DoS) condition. This vulnerability is due to insufficient handling of malformed packets. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
- How severe is CVE-2021-1431?
- CVE-2021-1431 has a CVSS 3.x base score of 7.5, 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-2021-1431 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-1431?
- CVE-2021-1431 primarily affects Cisco Ios Xe. In total, 32 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-1431?
- 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-2021-1431 published?
- CVE-2021-1431 was published on 2021-03-24 and last updated on 2026-06-17.
References
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-sdwdos-4zeEeC9w
Affected products (32)
- cpe:2.3:o:cisco:ios_xe:3.15.1xbs:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:3.15.2xbs:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.11.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.11.1a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.11.1b:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.11.1c:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.11.1s:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.11.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.1a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.1c:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.1s:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.1t:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.1w:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.1x:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.1y:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.1z:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.2a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.2s:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.2t:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.3a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.3s:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.4:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.12.4a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.2.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.2.1a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.2.1r:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.2.1v:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.2.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.2.3:*:*:*:*:*:*:*
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