Improper input validation in Cisco iOS Xe Software
CVE-2021-1356
Multiple vulnerabilities in the web UI of Cisco IOS XE Software could allow an authenticated, remote attacker with read-only privileges to cause the web UI software to become unresponsive and consume vty line instances, resulting in a denial of service (DoS) condition. These vulnerabilities are due to insufficient error handling in the web UI. An attacker could exploit these vulnerabilities by sending crafted HTTP packets to an affected device. A successful exploit could allow the attacker to cause the web UI software to become unresponsive and consume all available vty lines, preventing new session establishment and resulting in a DoS condition. Manual intervention would be required to regain web UI and vty session functionality. Note: These vulnerabilities do not affect the console connection.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.009 (59.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 59.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000
Affected products
- Cisco iOS Xe Software
- Cisco iOS Xe — versions 3.15.1xbs, 3.15.2xbs, 17.1.1
Weakness classification (CWE)
References
- tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xe-webui… (vendor-advisory, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-1356?
- CVE-2021-1356 is a medium-severity vulnerability in Cisco iOS Xe Software, classified under Improper Input Validation. CVSS score: 4.3/10. Published 2021-03-24.
- How severe is CVE-2021-1356?
- Medium severity. CVSS v3 base score is 4.3 out of 10.