CVE-2020-12021

mediumpriority · track · 37EPSS 0.016 · 75 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.57% (75th) EPSS

CVSS 6 · medium

Is it mine?

5 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cisa_csaf_ot · nvd

EPSS · scored 2026-10-27

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.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedPI Web API 2019cisa_csaf_ot
OSIsoft recommends affected users upgrade to PI Web API 2019 SP1.= OSIsoft also recommends affected users implement the following measures to reduce exploitation:
https://customers.osisoft.com/s/knowledgearticle?knowledgeArticleUrl=000028352
MitigationPI Web API 2019cisa_csaf_ot
Avoid adding authentication type anonymous in PI Web API configuration settings to limit exposure to authenticated users only.

cvss

Technical severity, 0–10. One row per scoring source.

9.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 6–9

v2.06mediumAV:N/AC:M/Au:S/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 6.8 · impact 6.4

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.3 · impact 6

v3.07.7highCVSS:3.0/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:Nsecondary · CISA US

v3.18.2highCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimaryCWE-79US

affected products (5)

Products and version ranges known to be affected.

PI Web API 2019: Patch 1 (1.12.0.6346) and all previous versionsall versionscisa_csaf_otUS
OSIsoft LLC PI Web API 2019≤ 1.12.0.6346cisa_csaf_otUS
n/a OSIsoft PI Web API 2019≤ OSIsoft PI Web API 2019 Patch 1 (1.12.0.6346) and all previous versionsenisa_euvdEU
osisoft pi web api≤ 2019nvdUScpe:2.3:a:osisoft:pi_web_api:*:*:*:*:*:*:*:*
osisoft pi web api= 2019nvdUScpe:2.3:a:osisoft:pi_web_api:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-20-163-01OSIsoft PI Web API 20192020-06-11icsa · cisa_csaf_otUS
Successful exploitation of this vulnerability could allow a remote authenticated attacker with write access to a PI Server to trick a user into interacting with a PI Web API endpoint that executes arbitrary JavaScript in the user 's browser, resulting in view, modification, or deletion of data as allowed for by the victim 's user permissions.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cisa_csaf_ot nvd NVD CVE.org MITRE

published 2020-06-23modified 2026-06-17

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+53051 more

references (7)

External citations — patches, advisories, analysis.

scry

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