CVE-2025-6021

mediumpriority · track · 0EPSS 0.014 · 72 %ileDEEUNLRUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.37% (72nd) EPSS

CVSS 6.5 · medium

Is it mine?

235 products

Check your exposure

Who says so?

8 sources

cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-21

A flaw was found in libxml2's xmlBuildQName function, where integer overflows in buffer size calculations can lead to a stack-based buffer overflow. This issue can result in memory corruption or a denial of service when processing crafted input.

remediations

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

A vendor fix is available.

FixedSIMATIC CN 4100siemens_psirt
Update to V5.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814144/
FixedRTU500 series CMU Firmwarecisa_csaf_ot
Update to CMU Firmware version 12.7.8
FixedSIMATIC CN 4100cisa_csaf_ot
Update to V5.0 or later version
https://support.industry.siemens.com/cs/ww/en/view/109814144/
MitigationRTU500 series CMU Firmwarecisa_csaf_ot
Follow general mitigation factors/workarounds.

cvss

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

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.5–7.5

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · CISA US

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · secalert@redhat.com USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · Siemens ProductCERT DE

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · NCSC-NL NL

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-121USCWE-121USCWE-121USCWE-190USCWE-787USCWE-787USCWE-787US

affected products (235)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Dell Avamarall versionscert_bundDEcpe:/a:dell:avamar:-
Dell NetWorkerall versionscert_bundDEcpe:/a:dell:networker:-
Dell NetWorker Virtual Editionall versionscert_bundDEcpe:/a:dell:networker:virtual_edition
Hitachi Energy RTU500all versionscert_bundDEcpe:/h:abb:rtu500:-
IBM AIX 7.2all versionscert_bundDEcpe:/o:ibm:aix:7.2
IBM AIX 7.3all versionscert_bundDEcpe:/o:ibm:aix:7.3
IBM MQ Operatorall versionscert_bundDEcpe:/a:ibm:mq:operator
IBM MQ containerall versionscert_bundDEcpe:/a:ibm:mq:container
IBM Power Hardware Management Console V10all versionscert_bundDEcpe:/a:ibm:hardware_management_console:v10
IBM Power Hardware Management Console v11all versionscert_bundDEcpe:/a:ibm:hardware_management_console:v11
IBM TXSeries for multiplatforms 11.1all versionscert_bundDEcpe:/a:ibm:txseries:for_multiplatforms_11.1
IBM VIOS 3.1all versionscert_bundDEcpe:/a:ibm:vios:3.1
IBM VIOS 4.1all versionscert_bundDEcpe:/a:ibm:vios:4.1
NetApp Data ONTAP 9all versionscert_bundDEcpe:/a:netapp:data_ontap:9
Open Source Arch Linuxall versionscert_bundDEcpe:/o:archlinux:archlinux:-
Open Source libxml2all versionscert_bundDEcpe:/a:xmlsoft:libxml2:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Red Hat OpenShift Container Platform 4.11all versionscert_bundDEcpe:/a:redhat:openshift:container_platform_4.11

showing 20 of 235

advisories (13)

Vendor and ecosystem advisories describing this.

NCSC-2026-0030Kwetsbaarheden verholpen in Oracle JavaNL2026-01-21csaf · ncsc_nlNL
Oracle heeft kwetsbaarheden verholpen in Oracle Java SE.
NCSC-2026-0147Kwetsbaarheden verholpen in Siemens-productenNL2026-05-13csaf · ncsc_nlNL
Siemens heeft kwetsbaarheden verholpen in verschillende (OT-)producten. Het gaat onder andere om producten in de Siemens RUGGEDCOM-, SCALANCE-, SIMATIC-, SIMIT-, SINAMICS-, SIPROTEC-, SENTRON- en Solid Edge-productreeksen.
SSA-032379SSA-032379: Multiple Vulnerabilities in SIMATIC CN 4100 Before V5.02026-05-12csaf · siemens_psirtDE
SIMATIC CN 4100 contains multiple vulnerabilities which could potentially lead to a compromise in availability, integrity and confidentiality. Siemens has released a new version for SIMATIC CN 4100 and recommends to update to the latest version.
WID-SEC-W-2025-1312libxml2: Mehrere Schwachstellen ermöglichen Denial of ServiceDeutsch2025-06-11csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in libxml2 ausnutzen, um einen Denial of Service Angriff durchzuführen oder nicht näher beschriebene Auswirkungen zu erzielen.
WID-SEC-W-2025-1905IBM QRadar SIEM Komponente: Mehrere SchwachstellenDeutsch2025-08-25csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM QRadar SIEM Komponenten ausnutzen, um Daten zu manipulieren, um einen Denial of Service Angriff durchzuführen, um beliebigen Programmcode auszuführen, um Sicherheitsvorkehrungen zu umgehen, und um Informationen offenzulegen.
WID-SEC-W-2026-0164Oracle Java SE: Mehrere SchwachstellenDeutsch2026-01-20csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Oracle Java SE ausnutzen, um die Vertraulichkeit, Integrität und Verfügbarkeit zu gefährden.
WID-SEC-W-2026-1118Dell PowerProtect Data Domain OS: Mehrere SchwachstellenDeutsch2026-04-14csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell PowerProtect Data Domain OS ausnutzen, um beliebigen Code auszuführen – sogar mit Root-Rechten –, um erweiterte Rechte zu erlangen – einschließlich Administratorrechte –, um Sicherheitsmaßnahmen zu umgehen, um Daten zu manipulieren, um vertrauliche Informationen offenzulegen oder um andere, nicht näher spezifizierte Angriffe durchzuführen.
WID-SEC-W-2026-2189Dell PowerProtect Data Domain: Mehrere SchwachstellenDeutsch2026-07-02csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Dell PowerProtect Data Domain ausnutzen, um seine Privilegien zu erhöhen um beliebigen Programmcode auszuführen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen, um einen Cross-Site Scripting Angriff durchzuführen, um Informationen offenzulegen, und um Dateien zu manipulieren.
ICSA-25-259-02Hitachi Energy RTU500 Series2025-09-09icsa · cisa_csaf_otUS
Hitachi Energy is aware of multiple vulnerabilities that affect the RTU500 versions that are listed below. An attacker successfully exploiting these vulnerabilities could potentially cause Denial of Service (DoS) impact on RTU500. Please refer to the Recommended Immediate Actions for information about the available mitigation/remediation strategies.
ICSA-26-134-10Siemens SIMATIC2026-05-12icsa · cisa_csaf_otUS
SIMATIC CN 4100 contains multiple vulnerabilities which could potentially lead to a compromise in availability, integrity and confidentiality. Siemens has released a new version for SIMATIC CN 4100 and recommends to update to the latest version.
BIT-java-2025-6021Libxml2: integer overflow in xmlbuildqname() leads to stack buffer overflow in libxml22026-05-06vendor · osvUS
A flaw was found in libxml2's xmlBuildQName function, where integer overflows in buffer size calculations can lead to a stack-based buffer overflow. This issue can result in memory corruption or a denial of service when processing crafted input.
BIT-java-min-2025-6021Libxml2: integer overflow in xmlbuildqname() leads to stack buffer overflow in libxml22026-05-06vendor · osvUS
A flaw was found in libxml2's xmlBuildQName function, where integer overflows in buffer size calculations can lead to a stack-based buffer overflow. This issue can result in memory corruption or a denial of service when processing crafted input.
BIT-jre-2025-6021Libxml2: integer overflow in xmlbuildqname() leads to stack buffer overflow in libxml22026-05-08vendor · osvUS
A flaw was found in libxml2's xmlBuildQName function, where integer overflows in buffer size calculations can lead to a stack-based buffer overflow. This issue can result in memory corruption or a denial of service when processing crafted input.

also known as (7)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu osv cert_bund ncsc_nl siemens_psirt cisa_csaf_ot NVD CVE.org MITRE

published 2025-06-12modified 2026-09-01

references (77)

External citations — patches, advisories, analysis.

scry

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