How severe is CVE-2020-27636?

CVE-2020-27636 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2020-27636 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-27636?

CVE-2020-27636 affects Microchip Mplab Network Creator. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-27636?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2020-27636 published?

CVE-2020-27636 was published on 2023-10-10 and last updated on 2026-06-17.

CVE-2020-27636

CVE-2020-27636 is a critical-severity vulnerability in Microchip Mplab Network Creator with a CVSS 3.x base score of 9.1. 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-330.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-330
Affected product: Microchip Mplab Network Creator
Published: 2023-10-10
Last modified: 2026-06-17

Description

In Microchip MPLAB Net 3.6.1, TCP ISNs are improperly random.

Frequently asked questions

What is CVE-2020-27636?: In Microchip MPLAB Net 3.6.1, TCP ISNs are improperly random.
How severe is CVE-2020-27636?: CVE-2020-27636 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2020-27636 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-27636?: CVE-2020-27636 affects Microchip Mplab Network Creator. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-27636?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-27636 published?: CVE-2020-27636 was published on 2023-10-10 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:microchip:mplab_network_creator:3.6.1:*:*:*:*:*:*:*

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