How severe is CVE-2020-4102?

CVE-2020-4102 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-4102 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-4102?

CVE-2020-4102 primarily affects Hcltech Notes. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-4102?

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

When was CVE-2020-4102 published?

CVE-2020-4102 was published on 2020-12-02 and last updated on 2026-06-17.

CVE-2020-4102

CVE-2020-4102 is a medium-severity vulnerability in Hcltech Notes with a CVSS 3.x base score of 6.7. 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-120.

Key facts

Severity: Medium (CVSS 3.x base score 6.7)
CVSS v2: 7.2
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Hcltech Notes
Published: 2020-12-02
Last modified: 2026-06-17

Description

HCL Notes is susceptible to a Buffer Overflow vulnerability in DXL due to improper validation of user input. A successful exploit could enable an attacker to crash Notes or execute attacker-controlled code on the client system.

Frequently asked questions

What is CVE-2020-4102?: HCL Notes is susceptible to a Buffer Overflow vulnerability in DXL due to improper validation of user input. A successful exploit could enable an attacker to crash Notes or execute attacker-controlled code on the client system.
How severe is CVE-2020-4102?: CVE-2020-4102 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-4102 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-4102?: CVE-2020-4102 primarily affects Hcltech Notes. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-4102?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-4102 published?: CVE-2020-4102 was published on 2020-12-02 and last updated on 2026-06-17.

References

https://support.hcltechsw.com/csm?id=kb_article&sysparm_article=KB0085499

Affected products (10)

cpe:2.3:a:hcltech:notes:*:*:*:*:*:*:*:*
cpe:2.3:a:hcltech:notes:10.0:*:*:*:*:*:*:*
cpe:2.3:a:hcltech:notes:10.0.1:-:*:*:*:*:*:*
cpe:2.3:a:hcltech:notes:10.0.1:fp1:*:*:*:*:*:*
cpe:2.3:a:hcltech:notes:10.0.1:fp2:*:*:*:*:*:*
cpe:2.3:a:hcltech:notes:10.0.1:fp3:*:*:*:*:*:*
cpe:2.3:a:hcltech:notes:10.0.1:fp4:*:*:*:*:*:*
cpe:2.3:a:hcltech:notes:10.0.1:fp5:*:*:*:*:*:*
cpe:2.3:a:hcltech:notes:11.0:*:*:*:*:*:*:*
cpe:2.3:a:hcltech:notes:11.0.1:*:*:*:*:*:*:*

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