CVE-2021-42567

mediumpriority · track · 27EPSS 0.082 · 95 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

8.19% (95th) EPSS

CVSS 4.3 · medium

Is it mine?

8 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-28

Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints.

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

v3.16.1mediumCVSS: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-79US

affected products (8)

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 n/a≤ n/aenisa_euvdEU
apereo central authentication service6.3.0 → 6.3.7.1nvdUScpe:2.3:a:apereo:central_authentication_service:*:*:*:*:*:*:*:*
apereo central authentication service6.4.0 → 6.4.2nvdUScpe:2.3:a:apereo:central_authentication_service:*:*:*:*:*:*:*:*
Maven org.apereo.cas:cas-server-core-web< 6.4.2osvUSpkg:maven/org.apereo.cas/cas-server-core-web

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-gfhx-jjwq-63gvCross-site Scripting in Apereo CAS2021-12-10ghsa · osvUS
Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd osv NVD CVE.org MITRE

published 2021-12-07modified 2026-06-17

related (53,073)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2026-42897US	medium6.1OT critical	70.7% (99th)	KEV	2026-05-14
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network…
CVE-2025-66376US	medium6.1OT critical	20.2% (97th)	KEV	2026-01-05
Zimbra Collaboration (ZCS) 10 before 10.0.18 and 10.1 before 10.1.13 allows Classic UI stored XSS via Cascading Style Sheets (CSS) @import directives in an HTML e-mail message.
CVE-2025-68461US	medium6.1OT critical	27.4% (98th)	KEV	2025-12-18
Roundcube Webmail before 1.5.12 and 1.6 before 1.6.12 is prone to a Cross-Site-Scripting (XSS) vulnerability via the animate tag in an SVG document.
CVE-2025-48700US	—OT critical	1.71% (77th)	KEV	2025-06-23
An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0 and 10.0 and 10.1. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to exec…
CVE-2025-27915US	—OT critical	4.06% (91st)	KEV	2025-03-12
An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Classic Web Client due to insufficient…

+53068 more

references (6)

External citations — patches, advisories, analysis.

https://apereo.github.io/2021/10/18/restvuln/cnnvd
https://github.com/apereo/cas/releases cnnvd
https://apereo.github.io/2021/10/18/restvuln/enisa_euvd
https://github.com/apereo/cas/releases enisa_euvd
https://apereo.github.io/2021/10/18/restvuln/PatchThird Party Advisorynvd
https://github.com/apereo/cas/releasesRelease NotesThird Party Advisorynvd

scry

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