CVE-2021-1312 json
Cisco Elastic Services Controller Denial of Service Vulnerability
published 2021-01-20 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6779
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.6%
- EPSS 2.6% chance of exploitation in 30 days, percentile 85%
- public exploits
- 0
- none known
Summary
A vulnerability in the system resource management of Cisco Elastic Services Controller (ESC) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) to the health monitor API on an affected device. The vulnerability is due to inadequate provisioning of kernel parameters for the maximum number of TCP connections and SYN backlog. An attacker could exploit this vulnerability by sending a flood of crafted TCP packets to an affected device. A successful exploit could allow the attacker to block TCP listening ports that are used by the health monitor API. This vulnerability only affects customers who use the health monitor API.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 2 y ago
Exploit prediction
2.56% chance of exploitation in the next 30 days, higher than 85% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- Cisco Cisco Elastic Services Controller
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
Sources
- CVE List CVE-2021-1312
- NVD CVE-2021-1312
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