CVE-2021-1436
CVE-2021-1436 is a medium-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 4.4. 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-22.
Key facts
- Severity: Medium (CVSS 3.x base score 4.4)
- CVSS v2: 4.7
- EPSS exploit prediction: 0% (23rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-22
- Affected product: Cisco Ios Xe
- Published:
- Last modified:
Description
A vulnerability in the CLI of Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to conduct path traversal attacks and obtain read access to sensitive files on an affected system. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted request to an affected system. A successful exploit could allow the attacker to view arbitrary files on the affected system.
Frequently asked questions
- What is CVE-2021-1436?
- A vulnerability in the CLI of Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to conduct path traversal attacks and obtain read access to sensitive files on an affected system. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted request to an affected system. A successful exploit could allow the attacker to view arbitrary files on the affected system.
- How severe is CVE-2021-1436?
- CVE-2021-1436 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
- Is CVE-2021-1436 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-1436?
- CVE-2021-1436 primarily affects Cisco Ios Xe. In total, 37 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-1436?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-1436 published?
- CVE-2021-1436 was published on 2021-03-24 and last updated on 2026-06-17.
References
Affected products (37)
- 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:16.12.1za:*:*:*:*:*:*:*
- 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:17.1.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.1.1a:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.1.1s:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.1.1t:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.1.2:*:*:*:*:*:*:*
- 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:*:*:*:*:*:*:*
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