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CVE Record

CVE-2026-34601: xmldom: XML injection via unsafe CDATA serialization allows attacker-controlled markup insertion

xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) `DOMParser` and `XMLSerializer` module. In xmldom versions 0.6.0 and prior and @xmldom/xmldom prior to versions 0.8.12 and 0.9.9, xmldom/xmldom allows attacker-controlled strings containing the CDATA terminator ]]> to be inserted into a CDATASection node. During serialization, XMLSerializer emitted the CDATA content verbatim without rejecting or safely splitting the terminator. As a result, data intended to remain text-only became active XML markup in the serialized output, enabling XML structure injection and downstream business-logic manipulation. This issue has been patched in xmldom version 0.6.0 and @xmldom/xmldom versions 0.8.12 and 0.9.9.

HighCVSS 7.5Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

A vulnerable xmldom XML serializer can let attacker-supplied text break out of a CDATA section and become real XML markup. This can corrupt or manipulate downstream XML-based business logic. The strongest known impact is integrity loss, not data theft or service outage.

Executive priority

Prioritize remediation for internet-facing or integration-heavy services where XML output changes business records, permissions, financial transactions, or partner messages. Treat as high urgency when untrusted input reaches XML serialization; otherwise schedule through normal dependency patching.

Technical view

The flaw is unsafe CDATA serialization. Inputs containing the CDATA terminator can be inserted into a CDATASection and emitted verbatim by XMLSerializer, allowing XML structure injection. Affected ranges are xmldom <= 0.6.0, @xmldom/xmldom < 0.8.12, and @xmldom/xmldom >= 0.9.0 < 0.9.9.

Likely exposure

Exposure is most likely in Node.js or JavaScript services that parse, build, or serialize XML using xmldom or @xmldom/xmldom, especially where user-controlled data is written into CDATA and later trusted by another XML consumer.

Exploitation context

The provided sources do not show active exploitation, and KEV is false. The CVSS vector indicates network reachability, low attack complexity, no privileges, and no user interaction, but practical impact depends on whether serialized XML drives trusted decisions downstream.

Researcher notes

This is CWE-91 XML injection through serialization, not parser entity expansion. The key research question is data flow: attacker-controlled CDATA content, xmldom serialization, and a downstream XML consumer that treats injected elements or attributes as authoritative.

Mitigation direction

  • Upgrade @xmldom/xmldom to 0.8.12, 0.9.9, or later as applicable.
  • Review vendor guidance for legacy xmldom because the bundle has inconsistent fixed-version wording.
  • Avoid placing untrusted strings into CDATA without validation or safe serialization controls.
  • Check downstream XML consumers for trust decisions based on serialized xmldom output.

Validation and detection

  • Inventory package-lock, yarn.lock, pnpm-lock, and SBOM entries for xmldom or @xmldom/xmldom.
  • Confirm running builds do not resolve to the affected version ranges.
  • Review code paths creating CDATASection nodes from user-controlled or partner-controlled input.
  • Trace serialized XML into business rules, signatures, imports, integrations, or authorization decisions.
  • Record whether vendor release notes or advisory status confirm remediation for your exact package line.
Prepared
Confidence
high
Sources
9

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

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ATT&CK lookup starting points

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cwe · low confidence lookup

CWE-91: Exact CWE lookup

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cve · low confidence lookup

CVE-2026-34601 mapping review

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Vulnerability profileCVE Program record
Severity
High
CVSS
7.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

2CVSS vectors
5Timeline events
2ADP providers
8Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: pocAutomatable: yesTechnical Impact: partial

CVSS vector scores

2 official scores

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N3.93.6GitHub_M
7.5CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N3.93.6redhat-SADP

Vulnerability scoring details

Base CVSS 3.1 score

7.5High
CVSS 3.1 vector shape for CVE-2026-34601Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. ADP timelineredhat-SADP

    Made public.

  3. CVE publishedCVE Program

    The CVE record was published.

  4. ADP timelineredhat-SADP

    Reported to Red Hat.

  5. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
redhat-SADPxmldom: xmldom: XML structure injection via CDATA terminator
other:Red Hat severity ratingcvssV3_1
  • 2026-04-02T19:03:40.667Z: Reported to Red Hat.
  • 2026-04-02T17:47:13.209Z: Made public.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
xmldomxmldomxmldom <= 0.6.0, @xmldom/xmldom < 0.8.12, @xmldom/xmldom >= 0.9.0, < 0.9.9Listed
Weakness

CWE details

CWE-91

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.

CWE-91 · source CWE mapping

XML Injection (aka Blind XPath Injection)

XML Injection (aka Blind XPath Injection) represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs