CVE-2021-1352
CVE-2021-1352 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-119.
Key facts
- Severity: High (CVSS 3.x base score 7.4)
- CVSS v2: 2.9
- EPSS exploit prediction: 0% (32nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-119
- Affected product: Cisco Ios Xe
- Published:
- Last modified:
Description
A vulnerability in the DECnet Phase IV and DECnet/OSI protocol processing of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient input validation of DECnet traffic that is received by an affected device. An attacker could exploit this vulnerability by sending DECnet traffic to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.
Frequently asked questions
- What is CVE-2021-1352?
- A vulnerability in the DECnet Phase IV and DECnet/OSI protocol processing of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient input validation of DECnet traffic that is received by an affected device. An attacker could exploit this vulnerability by sending DECnet traffic to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.
- How severe is CVE-2021-1352?
- CVE-2021-1352 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-2021-1352 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-1352?
- CVE-2021-1352 primarily affects Cisco Ios Xe. In total, 89 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-1352?
- 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-2021-1352 published?
- CVE-2021-1352 was published on 2021-03-24 and last updated on 2026-06-17.
References
Affected products (89)
- cpe:2.3:o:cisco:ios_xe:16.4.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.4.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.4.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.5.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.5.1a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.5.1b:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.5.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.5.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.4:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.4a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.4s:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.5:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.5a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.5b:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.6:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.7:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.7a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.6.8:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.7.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.7.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.7.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.8.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.8.1a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.8.1b:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.8.1c:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.8.1s:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.8.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.8.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.1a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.1b:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.1c:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.1d:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.1s:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.2a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:16.9.2s:*:*:*:*:*:*:*
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