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CVE Record

CVE-2025-49794: Libxml: heap use after free (uaf) leads to denial of service (dos)

A use-after-free vulnerability was found in libxml2. This issue occurs when parsing XPath elements under certain circumstances when the XML schematron has the <sch:name path="..."/> schema elements. This flaw allows a malicious actor to craft a malicious XML document used as input for libxml, resulting in the program's crash using libxml or other possible undefined behaviors.

CriticalCVSS 9.1Not KEV-listedUpdated
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Glexia's TakeAutomated analysiscritical

Security readout for executives and security teams

Plain-English summary

CVE-2025-49794 is a libxml2 memory-safety flaw. A crafted XML document can crash software that uses libxml2 under specific Schematron/XPath parsing conditions. Because libxml2 is a common system library, exposure may be indirect through applications and platforms, not just visibly installed tools.

Executive priority

Treat as urgent for Linux platform and application owners, especially where XML is accepted from outside trusted systems. The main documented business impact is service disruption, but the critical rating and common library footprint justify expedited remediation planning.

Technical view

The issue is a heap use-after-free during XPath element parsing when XML Schematron includes sch:name elements with path attributes. Red Hat rates it critical with CVSS 3.1 score 9.1. Public text emphasizes denial of service and undefined behavior; it does not confirm code execution.

Likely exposure

Organizations using affected Red Hat libxml2 packages on RHEL 7 ELS, 8, 9, 10 variants, or affected OpenShift Container Platform 4.12 RHCOS should assess exposure. Risk is highest where services parse untrusted XML content or XML supplied by users, partners, or automated feeds.

Exploitation context

The CVE record is not marked KEV, and the provided sources do not show active exploitation. The CVSS vector indicates network attackability, low complexity, no privileges, and no user interaction. Real-world exploitability depends on applications exposing libxml2 XML parsing to attacker-controlled input.

Researcher notes

Focus validation on dependency reachability, not just package presence. The trigger involves Schematron sch:name path handling during XPath parsing. Sources provide affected Red Hat package streams and advisories, but not detailed exploit evidence. Avoid assuming exploitation in products unless the application actually processes attacker-controlled XML through libxml2.

Mitigation direction

  • Apply the relevant Red Hat security advisory updates for affected RHEL and OpenShift deployments.
  • Update libxml2 packages through supported vendor channels where applicable.
  • For OpenShift, follow Red Hat guidance for affected RHCOS/OCP updates.
  • Prioritize internet-facing or partner-facing systems that parse XML input.
  • If patch timing is delayed, reduce acceptance of untrusted XML where operationally feasible.

Validation and detection

  • Inventory installed libxml2 packages and compare against Red Hat affected package versions.
  • Check Red Hat errata applicability for each RHEL, EUS, AUS, E4S, TUS, or ELS channel.
  • Identify applications and containers that parse XML using system libxml2.
  • Confirm OpenShift 4.12 clusters are not running affected RHCOS builds.
  • Monitor XML-processing services for crashes or abnormal parser failures.
Prepared
Confidence
medium
Sources
12

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

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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cwe · low confidence lookup

CWE-825: Exact CWE lookup

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description · low confidence lookup

Container behavior lookup

The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.

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cve · low confidence lookup

CVE-2025-49794 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
Critical
CVSS
9.1 (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:H

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.

1CVSS vectors
5Timeline events
3ADP providers
33Source links

SSVC decision data

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

CVSS vector scores

1 official score

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
9.1CVSS 3.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H3.95.2redhat

Vulnerability scoring details

Base CVSS 3.1 score

9.1Critical
CVSS 3.1 vector shape for CVE-2025-49794Attack 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:H

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. Source timelineredhat

    Made public.

  2. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  3. Source timelineredhat

    Reported to Red Hat.

  4. CVE publishedCVE Program

    The CVE record was published.

  5. CVE updatedCVE Program

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

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
CVECVE Program Container
siemens-SADPADP container

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
Unknown vendorlibxml2libxml2, 0unaffected
Red HatRed Hat Enterprise Linux 10libxml2, 0:2.12.5-7.el10_0affected
Red HatRed Hat Enterprise Linux 7 Extended Lifecycle Supportlibxml2, 0:2.9.1-6.el7_9.10affected
Red HatRed Hat Enterprise Linux 8libxml2, 0:2.9.7-21.el8_10.1affected
Red HatRed Hat Enterprise Linux 8libxml2, 0:2.9.7-21.el8_10.1affected
Red HatRed Hat Enterprise Linux 8.2 Advanced Update Supportlibxml2, 0:2.9.7-9.el8_2.3affected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Supportlibxml2, 0:2.9.7-9.el8_4.6affected
Red HatRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-Onlibxml2, 0:2.9.7-9.el8_4.6affected
Red HatRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Supportlibxml2, 0:2.9.7-13.el8_6.10affected
Red HatRed Hat Enterprise Linux 8.6 Telecommunications Update Servicelibxml2, 0:2.9.7-13.el8_6.10affected
Red HatRed Hat Enterprise Linux 8.6 Update Services for SAP Solutionslibxml2, 0:2.9.7-13.el8_6.10affected
Red HatRed Hat Enterprise Linux 8.8 Telecommunications Update Servicelibxml2, 0:2.9.7-16.el8_8.9affected
Red HatRed Hat Enterprise Linux 8.8 Update Services for SAP Solutionslibxml2, 0:2.9.7-16.el8_8.9affected
Red HatRed Hat Enterprise Linux 9libxml2, 0:2.9.13-10.el9_6affected
Red HatRed Hat Enterprise Linux 9libxml2, 0:2.9.13-10.el9_6affected
Red HatRed Hat Enterprise Linux 9.0 Update Services for SAP Solutionslibxml2, 0:2.9.13-1.el9_0.5affected
Red HatRed Hat Enterprise Linux 9.2 Update Services for SAP Solutionslibxml2, 0:2.9.13-3.el9_2.7affected
Red HatRed Hat Enterprise Linux 9.4 Extended Update Supportlibxml2, 0:2.9.13-10.el9_4affected
Red HatRed Hat JBoss Core Services 2.4.62.SP2libxml2unaffected
Red HatRed Hat OpenShift Container Platform 4.12rhcos, 412.86.202510291903-0affected
Red HatRed Hat OpenShift Container Platform 4.13rhcos, 413.92.202510150118-0affected
Red HatRed Hat OpenShift Container Platform 4.14rhcos, 414.92.202510211419-0affected
Red HatRed Hat OpenShift Container Platform 4.17rhcos, 417.94.202510112152-0affected
Red HatRed Hat OpenShift Container Platform 4.18rhcos, 418.94.202510230424-0affected
Red HatRed Hat OpenShift Container Platform 4.19rhcos, 4.19.9.6.202510140714-0affected
Red HatRed Hat OpenShift Container Platform 4.20rhcos, 4.20.9.6.202509251656-0affected
Red HatRed Hat Web Terminal 1.11 on RHEL 9web-terminal/web-terminal-rhel9-operator, 1.11-19affected
Red HatRed Hat Web Terminal 1.11 on RHEL 9web-terminal/web-terminal-tooling-rhel9, 1.11-8affected
Red HatRed Hat Web Terminal 1.12 on RHEL 9web-terminal/web-terminal-tooling-rhel9, 1.12-4affected
Red HatRHOSS-1.36-RHEL-8openshift-serverless-1/logic-data-index-ephemeral-rhel8, 1.36.0-11affected
Weakness

CWE details

CWE-825

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

CWE-825 · source CWE mapping

Expired Pointer Dereference

Expired Pointer Dereference represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

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