CVE-2020-4089

HCL Notes is vulnerable to an information leakage vulnerability through its support for the 'mailto' protocol. This vulnerability could result in files from the user's filesystem or connected network filesystems being leaked to a third party. All versions of HCL Notes 9, 10 and 11 are affected.

Published: 2020-06-26 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-4089 is rated Moderate Risk (48.9/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.16%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-4089

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.36% 1.16% +0.81%
2 2026-03-04 0.34% 0.36% +0.02%
3 2026-03-01 — 0.34% —

Full EPSS history (35 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-4089

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2020-4089

Affected software / configurations for CVE-2020-4089

Vendor Product Version Raw CPE
hcltech notes 9.0 cpe:2.3:a:hcltech:notes:9.0:*:*:*:*:*:*:*
hcltech notes 10.0 cpe:2.3:a:hcltech:notes:10.0:*:*:*:*:*:*:*
hcltech notes 11.0 cpe:2.3:a:hcltech:notes:11.0:*:*:*:*:*:*:*

References for CVE-2020-4089

cvelogic Threat Intelligence