CVE-2020-12021

In OSIsoft PI Web API 2019 Patch 1 (1.12.0.6346) and all previous versions, the affected product is vulnerable to a cross-site scripting attack, which may allow an attacker to remotely execute arbitrary code.

Published: 2020-06-23 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-12021 is rated Moderate Risk (62.2/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.57%). 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-2020-12021

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 0.59% 1.57% +0.98%
2 2026-03-04 0.52% 0.59% +0.07%
3 2026-03-01 — 0.52% —

Full EPSS history (47 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-12021

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.0 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H 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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.3 6.0 [email protected]
6.0 2.0 MEDIUM
AV:N/AC:M/Au:S/C:P/I:P/A:P 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:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 6.8 6.4 [email protected]

Weakness enumeration for CVE-2020-12021

Affected software / configurations for CVE-2020-12021

Vendor Product Version Raw CPE
osisoft pi_web_api <= 2019 cpe:2.3:a:osisoft:pi_web_api:*:*:*:*:*:*:*:*
osisoft pi_web_api 2019 cpe:2.3:a:osisoft:pi_web_api:2019:patch_1:*:*:*:*:*:*

References for CVE-2020-12021

URL Tags
https://www.us-cert.gov/ics/advisories/icsa-20-163-01 Third Party Advisory US Government Resource
cvelogic Threat Intelligence