CVE-2021-20323

mediumpriority · attend · 47EPSS 0.372 · 99 %ileexploit · PoCDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

3 exploits · PoC

Likely / severe?

37.2% (99th) EPSS

CVSS 4.3 · medium

Is it mine?

10 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

A POST based reflected Cross Site Scripting vulnerability on has been identified in Keycloak.

cvss

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

6.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.16.1mediumAV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · FSTEC (BDU) RU

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nsecondary · OSV

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Hsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimaryCWE-79USCWE-79US

exploits (3)

Public proof-of-concept and weaponised exploit code.

Cappricio-Securities/CVE-2021-20323A POST based reflected Cross Site Scripting vulnerability on has been identified in Keycloak.PoC · poc_in_github
cscpwn0sec/CVE-2021-20323Exploitation Scanner Cross Site Scripting vulnerability in Keycloak.PoC · poc_in_github
ndmalc/CVE-2021-20323ndmalc/CVE-2021-20323PoC · poc_in_github

affected products (10)

Products and version ranges known to be affected.

Dell ECS <3.8.1.0all versionscert_bundDE
Dell PowerEdgeall versionscert_bundDEcpe:/h:dell:poweredge:-
IBM InfoSphere Information Serverall versionscert_bundDEcpe:/a:ibm:infosphere_information_server:-
Dell ECS< 3.8.1.0cert_bundDE
n/a keycloak-services≤ keycloak 17.0.0enisa_euvdEU
Red Hat Inc. Keycloak≤ 22.0.1fstec_bduRU
Red Hat Inc. Keycloak≤ 18.0.0fstec_bduRU
Red Hat Inc. Red Hat Single Sign-On≤ 7fstec_bduRU
redhat keycloak< 17.0.0nvdUScpe:2.3:a:redhat:keycloak:*:*:*:*:*:*:*:*
Maven org.keycloak:keycloak-core15.0.0 → 17.0.0osvUSpkg:maven/org.keycloak/keycloak-core

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2024-0794Dell ECS: Mehrere SchwachstellenDeutsch2024-04-04csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell ECS ausnutzen, um seine Privilegien zu erweitern, beliebigen Programmcode mit Administratorrechten auszuführen, Informationen offenzulegen, Dateien zu manipulieren, einen Cross-Site-Scripting-Angriff durchzuführen, Sicherheitsvorkehrungen zu umgehen oder einen Denial of Service Zustand herbeizuführen.
GHSA-xpgc-j48j-jwv9Cross-site Scripting in Keycloak2022-03-26ghsa · osvUS
A POST based reflected Cross Site Scripting vulnerability on has been identified in Keycloak version 15. The issue was fixed in version 17.0.0.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd osv NVD CVE.org MITRE

published 2022-03-25modified 2026-06-17

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+53004 more

references (4)

External citations — patches, advisories, analysis.

scry

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