How severe is CVE-2020-36997?

CVE-2020-36997 has a CVSS 3.x base score of 9.8, 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 high.

Is CVE-2020-36997 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2020-36997?

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.

Does CVE-2020-36997 have an EU (EUVD) identifier?

Yes. CVE-2020-36997 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-30909.

When was CVE-2020-36997 published?

CVE-2020-36997 was published on 2026-01-29 and last updated on 2026-06-17.

CVE-2020-36997

CVE-2020-36997 is a critical-severity vulnerability with a CVSS 3.x base score of 9.8. 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-121.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 8.4
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2020-30909
Weakness: CWE-121
Published: 2026-01-29
Last modified: 2026-06-17

Description

BacklinkSpeed 2.4 contains a buffer overflow vulnerability that allows attackers to corrupt the Structured Exception Handler (SEH) chain through malicious file import. Attackers can craft a specially designed payload file to overwrite SEH addresses, potentially executing arbitrary code and gaining control of the application.

Frequently asked questions

What is CVE-2020-36997?: BacklinkSpeed 2.4 contains a buffer overflow vulnerability that allows attackers to corrupt the Structured Exception Handler (SEH) chain through malicious file import. Attackers can craft a specially designed payload file to overwrite SEH addresses, potentially executing arbitrary code and gaining control of the application.
How severe is CVE-2020-36997?: CVE-2020-36997 has a CVSS 3.x base score of 9.8, 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 high.
Is CVE-2020-36997 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2020-36997?: 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.
Does CVE-2020-36997 have an EU (EUVD) identifier?: Yes. CVE-2020-36997 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-30909.
When was CVE-2020-36997 published?: CVE-2020-36997 was published on 2026-01-29 and last updated on 2026-06-17.

References

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