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Full vulnerability report · 2021
CVE-2021-23926High confidence

XMLBeans XML Entity Expansion

Apache Software Foundation · Apache XMLBeans

9.1CriticalCVSS 3.1
Recommended action
Within 72 hours

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.

Patch available
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-1365

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 72 hours

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.

Patch available
01

What, why and how

The XML parsers used by XMLBeans up to version 2.6.0 did not set the properties needed to protect the user from malicious XML input. Vulnerabilities include possibilities for XML Entity Expansion attacks. Affects XMLBeans up to and including v2.6.0.

What

The XML parsers used by XMLBeans up to version 2.6.0 did not set the properties needed to protect the user from malicious XML input. Vulnerabilities include possibilities for XML Entity Expansion attacks. Affects XMLBeans up to and including v2.6.0.

Why

The product uses XML documents and allows their structure to be defined with a Document Type Definition (DTD), but it does not properly control the number of recursive definitions of entities.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

The XML parsers used by XMLBeans up to version 2.6.0 did not set the properties needed to protect the user from malicious XML input. Vulnerabilities include possibilities for XML Entity Expansion attacks. Affects XMLBeans up to and including v2.6.0.

Why

The product uses XML documents and allows their structure to be defined with a Document Type Definition (DTD), but it does not properly control the number of recursive definitions of entities.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion') → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-776

CWE-776: Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion'). The product uses XML documents and allows their structure to be defined with a Document Type Definition (DTD), but it does not properly control the number of recursive definitions of entities.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-776
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-W-2026-0180Dell Data Protection Advisor: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Dell Data Protection Advisor ausnutzen, um beliebigen Code auszuführen, einen Denial-of-Service-Zustand zu erzeugen, Sicherheitsmaßnahmen zu umgehen und nicht näher spezifizierte Angriffe zu starten.

Official advisory
BSI · German · WID-SEC-W-2024-0068IBM Business Automation Workflow: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in IBM Business Automation Workflow ausnutzen, um beliebigen Programmcode auszuführen, Informationen offenzulegen, einen Denial of Service Zustand herbeizuführen oder Dateien zu manipulieren.

Official advisory
BSI · German · WID-SEC-W-2023-1807Oracle Fusion Middleware: Mehrere Schwachstellen

Ein Angreifer aus dem angrenzenden Netzwerk oder ein entfernter anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in Oracle Fusion Middleware ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.

Official advisory
BSI · German · WID-SEC-W-2024-0156IBM Business Automation Workflow: Mehrere Schwachstellen

Ein entfernter, anonymer oder authentisierter Angreifer kann mehrere Schwachstellen in IBM Business Automation Workflow ausnutzen, um einen Denial of Service Angriff durchzuführen und beliebigen Code zur Ausführung zu bringen.

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0556Multiples vulnérabilités dans les produits VMware

rg/CVERecord?id=CVE-2020-8840 Référence CVE CVE-2020-8908 https://www.cve.org/CVERecord?id=CVE-2020-8908 Référence CVE CVE-2020-9492 https://www.cve.org/CVERecord?id=CVE-2020-9492 Référence CVE CVE-2020-9546 https://www.cve.org/CVERecord?id=CVE-2020-9546 Référence CVE CVE-2020-9547 https://www.cve.org/CVERecord?id=CVE-2020-9547 Référence CVE CVE-2020-9548 https://www.cve.org/CVERecord?id=CVE-2020-9548 Référence CVE CVE-2021-20190 https://www.cve.org/CVERecord?id=CVE-2021-20190 Référence CVE CVE-2021-22569 https://www.cve.org/CVERecord?id=CVE-2021-22569 Référence CVE CVE-2021-22573 https://www.cve.org/CVERecord?id=CVE-2021-22573 Référence CVE CVE-2021-23926 https://www.cve.org/CVERecord?id=CVE-2021-23926 Référence CVE CVE-2021-27807 https://www.cve.org/CVERecord?id=CVE-2021-27807 Référence CVE CVE-2021-27906 https://www.cve.org/CVERecord?id=CVE-2021-27906 Référence CVE CVE-2021-29262 https://www.cve.org/CVERecord?id=CVE-2021-29262 Référence CVE CVE-2021-29425 https://www.cve.org/CVERecord?id=CVE-2021-29425 Référence CVE CVE-2021-31811 https://www.cve.org/CVERecord?id=CVE-2021-31811 Référence CVE CVE-2021-31812 https://www.cve.org/CVERecord?id=CVE-2021-31812 Référence CVE CVE-2021-35515 https://www.cve.org/CVERecord?id=CVE-2021-35515 Référence CVE CVE-2021-35516 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-951Multiples vulnérabilités dans le noyau Linux de RedHat

d?id=CVE-2021-21346 Référence CVE CVE-2021-21347 https://www.cve.org/CVERecord?id=CVE-2021-21347 Référence CVE CVE-2021-21348 https://www.cve.org/CVERecord?id=CVE-2021-21348 Référence CVE CVE-2021-21349 https://www.cve.org/CVERecord?id=CVE-2021-21349 Référence CVE CVE-2021-21350 https://www.cve.org/CVERecord?id=CVE-2021-21350 Référence CVE CVE-2021-21351 https://www.cve.org/CVERecord?id=CVE-2021-21351 Référence CVE CVE-2021-21409 https://www.cve.org/CVERecord?id=CVE-2021-21409 Référence CVE CVE-2021-22118 https://www.cve.org/CVERecord?id=CVE-2021-22118 Référence CVE CVE-2021-22696 https://www.cve.org/CVERecord?id=CVE-2021-22696 Référence CVE CVE-2021-23926 https://www.cve.org/CVERecord?id=CVE-2021-23926 Référence CVE CVE-2021-27568 https://www.cve.org/CVERecord?id=CVE-2021-27568 Référence CVE CVE-2021-28163 https://www.cve.org/CVERecord?id=CVE-2021-28163 Référence CVE CVE-2021-28164 https://www.cve.org/CVERecord?id=CVE-2021-28164 Référence CVE CVE-2021-28169 https://www.cve.org/CVERecord?id=CVE-2021-28169 Référence CVE CVE-2021-28170 https://www.cve.org/CVERecord?id=CVE-2021-28170 Référence CVE CVE-2021-29425 https://www.cve.org/CVERecord?id=CVE-2021-29425 Référence CVE CVE-2021-30129 https://www.cve.org/CVERecord?id=CVE-2021-30129 Référence CVE CVE-2021-30468 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-804Multiples vulnérabilités dans Oracle PeopleSoft

De multiples vulnérabilités ont été découvertes dans Oracle PeopleSoft. Elles permettent à un attaquant de provoquer un déni de service à distance, une atteinte à l'intégrité des données et une atteinte à la confidentialité des données.

Official advisory
CERT-FR · French · CERTFR-2021-AVI-770Multiples vulnérabilités dans les produits SAP

De multiples vulnérabilités ont été découvertes dans les produits SAP. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service, un contournement de la politique de sécurité et une atteinte à la confidentialité des données.

Official advisory
NCSC-NL · Dutch · NCSC-2026-0028Kwetsbaarheden verholpen in Oracle Analytics

Multiple vulnerabilities across Oracle products, including Middleware, Business Intelligence, and SOA Suite, as well as XMLBeans, expose systems to unauthorized access and denial of service, with CVSS scores ranging from 7.3 to 9.1.

Official advisory
NCSC-NL · Dutch · NCSC-2025-0028Kwetsbaarheden verholpen in Oracle Analytics

Een kwaadwillende kan de kwetsbaarheden misbruiken om een Denial-of-Service te veroorzaken, of zich toegang te verschaffen tot gevoelige gegevens.

Official advisory
NCSC-NL · Dutch · NCSC-2024-0299Kwetsbaarheden verholpen in Oracle Analytics

Een kwaadwillende kan de kwetsbaarheden misbruiken om aanvallen uit te voeren die kunnen leiden tot de volgende categorieën schade: * Denial-of-Service (DoS) * Toegang tot gevoelige gegevens * Toegang tot systeemgegevens * Manipulatie van gegevens * (Remote) code execution (Gebruikersrechten)

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
Apache XMLBeans ≤ 2.6.0
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 14 Jan 2021 · Last source change 13 Feb 2025, 16:27 UTC · CWE-776 · Improper Restriction of Recursive Entity References in DTDs ('XML Entity Expansion')

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-1365
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-23926 · cve.blacktree.nl