Is CVE-2011-1871 in the CISA KEV catalog?

No. CVE-2011-1871 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2011-1871?

CVE-2011-1871 has a CVSS v2 base score of 7.8 (HIGH).

What is the EPSS score for CVE-2011-1871?

CVE-2011-1871 has an EPSS score of 38.46% (98th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2011-1871

HIGHEPSS 98th pctl

7.8

CVSS v2

NVD

Description

Tcpip.sys in the TCP/IP stack in Microsoft Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 allows remote attackers to cause a denial of service (reboot) via a series of crafted ICMP messages, aka "ICMP Denial of Service Vulnerability."

CWE-399

CVSS v2 Vector

No CVSS vector data available.

Exploit Intelligence

38.46%probability of exploitation in 30 days

98thpercentile

Very high risk: more likely to be exploited than 98% of all known CVEs.

References

http://www.us-cert.gov/cas/techalerts/TA11-221A.html
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-064
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12971

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-29.