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Full vulnerability report · 2026
CVE-2026-1757High confidence

Libxml2: memory leak leading to local denial of service in xmllint interactive shell

Red Hat · Red Hat Hardened Images

Official source article: Red Hat RHSA-2026:7519 ↗. Check the applicable product and release in the original source.

6.2MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 0.22% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Red Hat Red Hat Hardened Images and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: As exposure requiresRemediation target: Within 365 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Distribution package intelligence

Release-specific package status

Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

4 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Debian trixietrixie · sourcelibxml2Vendor fix publishedDebian records a fixed source-package version for this release.2.12.7+dfsg+really2.9.14-2.1+deb13u3Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcelibxml2Vendor fix publishedDebian records a fixed source-package version for this release.2.9.14+dfsg-1.3~deb12u6Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcelibxml2Vendor fix publishedDebian records a fixed source-package version for this release.2.15.2+dfsg-0.1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcelibxml2Vendor fix publishedDebian records a fixed source-package version for this release.2.15.2+dfsg-0.1Debian Security Tracker ↗Source updated 5 Oct 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
CVE-2026-1757 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitylibxml2: Memory Leak Leading to Local Denial of Service in xmllint Interactive Shell
26 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • libxml2 as a component of Red Hat Enterprise Linux 10
  • libxml2-devel as a component of Red Hat Enterprise Linux 10
  • libxml2-static as a component of Red Hat Enterprise Linux 10
  • libxml2.src as a component of Red Hat Enterprise Linux 10
  • python3-libxml2 as a component of Red Hat Enterprise Linux 10
  • libxml2 as a component of Red Hat Enterprise Linux 6
  • libxml2-devel as a component of Red Hat Enterprise Linux 6
  • libxml2-python as a component of Red Hat Enterprise Linux 6
  • libxml2-static as a component of Red Hat Enterprise Linux 6
  • libxml2.src as a component of Red Hat Enterprise Linux 6
  • libxml2 as a component of Red Hat Enterprise Linux 7
  • libxml2-devel as a component of Red Hat Enterprise Linux 7
Summary
A flaw was identified in the interactive shell of the xmllint utility, part of the libxml2 project, where memory allocated for user input is not properly released under certain conditions. When a user submits input consisting only of whitespace, the program skips command execution but fails to free the allocated buffer. Repeating this action causes memory to continuously accumulate. Over time, this can exhaust system memory and terminate the xmllint process, creating a denial-of-service condition on the local system.
Remediation
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
Optional official sources

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

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

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-2026-5101

No EUVD known-exploited evidence

A flaw was identified in the interactive shell of the xmllint utility, part of the libxml2 project, where memory allocated for user input is not properly released under certain conditions. When a user submits input consisting only of whitespace, the program skips command execution but fails to free the allocated buffer. Repeating this action causes memory to continuously accumulate. Over time, this can exhaust system memory and terminate the xmllint process, creating a denial-of-service condition on the local system.

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
6.2 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

A flaw was identified in the interactive shell of the xmllint utility, part of the libxml2 project, where memory allocated for user input is not properly released under certain conditions. When a user submits input consisting only of whitespace, the program skips command execution but fails to free the allocated buffer. Repeating this action causes memory to continuously accumulate. Over time, this can exhaust system memory and terminate the xmllint process, creating a denial-of-service condition on the local system.

What

A flaw was identified in the interactive shell of the xmllint utility, part of the libxml2 project, where memory allocated for user input is not properly released under certain conditions. When a user submits input consisting only of whitespace, the program skips command execution but fails to free the allocated buffer. Repeating this action causes memory to continuously accumulate. Over time, this can exhaust system memory and terminate the xmllint process, creating a denial-of-service condition on the local system.

Why

The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

How

An attacker operating through local access 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

A flaw was identified in the interactive shell of the xmllint utility, part of the libxml2 project, where memory allocated for user input is not properly released under certain conditions. When a user submits input consisting only of whitespace, the program skips command execution but fails to free the allocated buffer. Repeating this action causes memory to continuously accumulate. Over time, this can exhaust system memory and terminate the xmllint process, creating a denial-of-service condition on the local system.

Why

The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

How

An attacker operating through local access 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
local access → Missing Release of Memory after Effective Lifetime → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
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-401 ↗

CWE-401: Missing Release of Memory after Effective Lifetime. The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

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

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

AVLocalAttack vector: The attacker needs local access to the vulnerable system.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.CNoneConfidentiality impact: No direct loss is represented by this metric.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
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
UnauthenticatedCWE-401
A

Official authority intelligence

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

ENISA EUVD · EUVD-2026-5101Official EUVD mapping

A flaw was identified in the interactive shell of the xmllint utility, part of the libxml2 project, where memory allocated for user input is not properly released under certain conditions. When a user submits input consisting only of whitespace, the program skips command execution but fails to free the allocated buffer. Repeating this action causes memory to continuously accumulate. Over time, this can exhaust system memory and terminate the xmllint process, creating a denial-of-service condition on the local system.

Official EUVD record ↗
BSI · German · WID-SEC-2026-0284libxml2 (xmllint): Schwachstelle ermöglicht Denial of Service

Ein lokaler Angreifer kann eine Schwachstelle in libxml2 ausnutzen, um einen Denial of Service Angriff durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20260204Security Bulletin 04 Feb 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 04 Feb 2026, published on 4 February 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0266Multiples vulnérabilités dans VMware Tanzu

.cve.org/CVERecord?id=CVE-2026-0861 Référence CVE CVE-2026-0915 https://www.cve.org/CVERecord?id=CVE-2026-0915 Référence CVE CVE-2026-0988 https://www.cve.org/CVERecord?id=CVE-2026-0988 Référence CVE CVE-2026-0989 https://www.cve.org/CVERecord?id=CVE-2026-0989 Référence CVE CVE-2026-0990 https://www.cve.org/CVERecord?id=CVE-2026-0990 Référence CVE CVE-2026-0992 https://www.cve.org/CVERecord?id=CVE-2026-0992 Référence CVE CVE-2026-1484 https://www.cve.org/CVERecord?id=CVE-2026-1484 Référence CVE CVE-2026-1485 https://www.cve.org/CVERecord?id=CVE-2026-1485 Référence CVE CVE-2026-1489 https://www.cve.org/CVERecord?id=CVE-2026-1489 Référence CVE CVE-2026-1757 https://www.cve.org/CVERecord?id=CVE-2026-1757 Référence CVE CVE-2026-2100 https://www.cve.org/CVERecord?id=CVE-2026-2100 Référence CVE CVE-2026-22185 https://www.cve.org/CVERecord?id=CVE-2026-22185 Référence CVE CVE-2026-24883 https://www.cve.org/CVERecord?id=CVE-2026-24883 Référence CVE CVE-2026-26960 https://www.cve.org/CVERecord?id=CVE-2026-26960 Référence CVE CVE-2026-27171 https://www.cve.org/CVERecord?id=CVE-2026-27171 Gestion détaillée du document le 11 mars 2026 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr f

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
Fixed
Action
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 2 Feb 2026 · Last source change 1 Sept 2026, 11:54 UTC · CWE-401 · Missing Release of Memory after Effective Lifetime

CVE recordCVE.org · 5.2
CVSS sourceCNA
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-2026-5101
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD not scheduled

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

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    libxml2 as a component of Red Hat Enterprise Linux 10; libxml2-devel as a component of Red Hat Enterprise Linux 10; libxml2-static as a component of Red Hat Enterprise Linux 10; libxml2.src as a component of Red Hat Enterprise Linux 10; python3-libxml2 as a component of Red Hat Enterprise Linux 10; libxml2 as a component of Red Hat Enterprise Linux 6; libxml2-devel as a component of Red Hat Enterprise Linux 6; libxml2-python as a component of Red Hat Enterprise Linux 6; libxml2-static as a component of Red Hat Enterprise Linux 6; libxml2.src as a component of Red Hat Enterprise Linux 6; libxml2 as a component of Red Hat Enterprise Linux 7; libxml2-devel as a component of Red Hat Enterprise Linux 7; libxml2-python as a component of Red Hat Enterprise Linux 7; libxml2-static as a component of Red Hat Enterprise Linux 7; libxml2.src as a component of Red Hat Enterprise Linux 7; libxml2 as a component of Red Hat Enterprise Linux 8; libxml2-devel as a component of Red Hat Enterprise Linux 8; libxml2.src as a component of Red Hat Enterprise Linux 8; python3-libxml2 as a component of Red Hat Enterprise Linux 8; libxml2 as a component of Red Hat Enterprise Linux 9; libxml2-devel as a component of Red Hat Enterprise Linux 9; libxml2.src as a component of Red Hat Enterprise Linux 9; python3-libxml2 as a component of Red Hat Enterprise Linux 9; libxml2 as a component of Red Hat JBoss Core Services; openshift/ose-rhel-coreos-9 as a component of Red Hat OpenShift Container Platform 4 · Fixed: libxml2-main@aarch64 as a component of Red Hat Hardened Images; libxml2-main@src as a component of Red Hat Hardened Images; libxml2-main@x86_64 as a component of Red Hat Hardened Images
    After
    libxml2 as a component of Red Hat Enterprise Linux 10; libxml2-devel as a component of Red Hat Enterprise Linux 10; libxml2-static as a component of Red Hat Enterprise Linux 10; libxml2.src as a component of Red Hat Enterprise Linux 10; python3-libxml2 as a component of Red Hat Enterprise Linux 10; libxml2 as a component of Red Hat Enterprise Linux 6; libxml2-devel as a component of Red Hat Enterprise Linux 6; libxml2-python as a component of Red Hat Enterprise Linux 6; libxml2-static as a component of Red Hat Enterprise Linux 6; libxml2.src as a component of Red Hat Enterprise Linux 6; libxml2 as a component of Red Hat Enterprise Linux 7; libxml2-devel as a component of Red Hat Enterprise Linux 7; libxml2-python as a component of Red Hat Enterprise Linux 7; libxml2-static as a component of Red Hat Enterprise Linux 7; libxml2.src as a component of Red Hat Enterprise Linux 7; libxml2 as a component of Red Hat Enterprise Linux 8; libxml2-devel as a component of Red Hat Enterprise Linux 8; libxml2.src as a component of Red Hat Enterprise Linux 8; python3-libxml2 as a component of Red Hat Enterprise Linux 8; libxml2 as a component of Red Hat Enterprise Linux 9; libxml2-devel as a component of Red Hat Enterprise Linux 9; libxml2.src as a component of Red Hat Enterprise Linux 9; python3-libxml2 as a component of Red Hat Enterprise Linux 9; libxml2 as a component of Red Hat JBoss Core Services; openshift/ose-rhel-coreos-8 as a component of Red Hat OpenShift Container Platform 4; openshift/ose-rhel-coreos-9 as a component of Red Hat OpenShift Container Platform 4 · Fixed: libxml2-main@aarch64 as a component of Red Hat Hardened Images; libxml2-main@src as a component of Red Hat Hardened Images; libxml2-main@x86_64 as a component of Red Hat Hardened Images
    Red Hat Product Security ↗
  2. Affected versionsThe structured affected or fixed version information changed.
    Before
    See the vendor and CVE records for the affected range. · Fixed: 2.15.2-0.3.hum1 < *
    After
    See the vendor and CVE records for the affected range. · Fixed: Red Hat Hardened Images: 2.15.2-0.3.hum1 < *
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2026-5101↗Vendor CSAF · Red Hat Product Security↗CVE authority or vendor reference · Red Hat RHSA-2026:7519↗Official CVE record (CNA and ADP data)↗NVD record↗
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-2026-1757 · cve.blacktree.nl