How severe is CVE-2011-4871?

CVE-2011-4871 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2011-4871 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2011-4871?

CVE-2011-4871 affects Opcsystems Opcsystems.net. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2011-4871?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2011-4871 published?

CVE-2011-4871 was published on 2012-04-18 and last updated on 2026-06-16.

CVE-2011-4871

CVE-2011-4871 is a medium-severity vulnerability in Opcsystems Opcsystems.net with a CVSS 2.0 base score of 5.0. 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-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Opcsystems Opcsystems.net
Published: 2012-04-18
Last modified: 2026-06-16

Description

Open Automation Software OPC Systems.NET before 5.0 allows remote attackers to cause a denial of service via a malformed .NET RPC packet on TCP port 58723.

Frequently asked questions

What is CVE-2011-4871?: Open Automation Software OPC Systems.NET before 5.0 allows remote attackers to cause a denial of service via a malformed .NET RPC packet on TCP port 58723.
How severe is CVE-2011-4871?: CVE-2011-4871 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2011-4871 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2011-4871?: CVE-2011-4871 affects Opcsystems Opcsystems.net. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2011-4871?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2011-4871 published?: CVE-2011-4871 was published on 2012-04-18 and last updated on 2026-06-16.

References

http://www.us-cert.gov/control_systems/pdf/ICSA-12-012-01.pdf

Affected products (1)

cpe:2.3:a:opcsystems:opcsystems.net:*:*:*:*:*:*:*:*

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