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Full vulnerability report · 2026
CVE-2026-115327High confidence

libyang through 6.4.13 Uninitialized Pointer Free in NETCONF RPC Parser

CESNET · libyang

6.0MediumCVSS 4.0
Recommended action
Patch only the product branches with a verified fix

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 82 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
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 0.31% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs CESNET libyang 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.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 82 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

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
Package result overrides the generic status

BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 4 affected package states shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.

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 · sourcelibyangAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 23 Oct 2026
Debian bookwormbookworm · sourcelibyang2Affected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 23 Oct 2026
Debian forkyforky · sourcelibyangAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 23 Oct 2026
Debian sidsid · sourcelibyangAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 23 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.

2 current
CVE-2026-115327 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitylibyang: libyang: Denial of Service via crafted NETCONF RPC action envelope
8 known affected

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

  • libyang as a component of Red Hat Enterprise Linux 10
  • libyang-devel as a component of Red Hat Enterprise Linux 10
  • libyang-devel-doc as a component of Red Hat Enterprise Linux 10
  • libyang.src as a component of Red Hat Enterprise Linux 10
  • libyang as a component of Red Hat Enterprise Linux 9
  • libyang-devel as a component of Red Hat Enterprise Linux 9
  • libyang-devel-doc as a component of Red Hat Enterprise Linux 9
  • libyang.src as a component of Red Hat Enterprise Linux 9
Summary
A flaw was found in libyang. An uninitialized pointer free vulnerability occurs during the processing of Network Configuration Protocol (NETCONF) Remote Procedure Call (RPC) action envelopes. An authenticated remote attacker with an established NETCONF session can trigger this flaw by sending a specially crafted action request containing unexpected text data. Successful exploitation can lead to a Denial of Service (DoS) through application crashes or cause memory corruption.
Remediation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
CVE-2026-115327 · CSAF 2.0 · revision 2 · interimSUSE Product Security TeamCVE-2026-115327
70 known affected

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

  • libyang as component of SUSE Linux Enterprise High Performance Computing 12 SP5
  • libyang2 as component of SUSE Linux Enterprise High Performance Computing 12 SP5
  • libyang as component of SUSE Linux Enterprise High Performance Computing 15 SP3
  • libyang-extentions as component of SUSE Linux Enterprise High Performance Computing 15 SP3
  • libyang1 as component of SUSE Linux Enterprise High Performance Computing 15 SP3
  • libyang as component of SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
  • libyang-extentions as component of SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
  • libyang1 as component of SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS
  • libyang as component of SUSE Linux Enterprise High Performance Computing 15 SP4
  • libyang-extentions as component of SUSE Linux Enterprise High Performance Computing 15 SP4
  • libyang1 as component of SUSE Linux Enterprise High Performance Computing 15 SP4
  • libyang as component of SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS
Summary
libyang through 6.4.13 contains an uninitialized pointer free vulnerability in lydxml_env_netconf_rpc() in src/parser_xml.c when parsing NETCONF rpc action envelopes. Peers with a NETCONF session can send an action element containing non-whitespace text via lyd_parse_op() to crash servers like netopeer2 or corrupt the heap.
Remediation
No remediation text is recorded.
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-2026-108129

No EUVD known-exploited evidence

libyang through 6.4.13 contains an uninitialized pointer free vulnerability in lydxml_env_netconf_rpc() in src/parser_xml.c when parsing NETCONF rpc action envelopes. Peers with a NETCONF session can send an action element containing non-whitespace text via lyd_parse_op() to crash servers like netopeer2 or corrupt the heap.

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
6.0 · CVSS 4.0
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch only the product branches with a verified fix

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority. Verified remediation exists for at least one product or source, but 82 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

libyang through 6.4.13 contains an uninitialized pointer free vulnerability in lydxml_env_netconf_rpc() in src/parser_xml.c when parsing NETCONF rpc action envelopes. Peers with a NETCONF session can send an action element containing non-whitespace text via lyd_parse_op() to crash servers like netopeer2 or corrupt the heap.

What

libyang through 6.4.13 contains an uninitialized pointer free vulnerability in lydxml_env_netconf_rpc() in src/parser_xml.c when parsing NETCONF rpc action envelopes. Peers with a NETCONF session can send an action element containing non-whitespace text via lyd_parse_op() to crash servers like netopeer2 or corrupt the heap.

Why

The product accesses or uses a pointer that has not been initialized.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

What

libyang through 6.4.13 contains an uninitialized pointer free vulnerability in lydxml_env_netconf_rpc() in src/parser_xml.c when parsing NETCONF rpc action envelopes. Peers with a NETCONF session can send an action element containing non-whitespace text via lyd_parse_op() to crash servers like netopeer2 or corrupt the heap.

Why

The product accesses or uses a pointer that has not been initialized.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

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 → Access of Uninitialized Pointer → disrupt the affected service
Attack surface
Network
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
Security boundary
Not a CVSS 4.0 base metric
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-824 ↗

CWE-824: Access of Uninitialized Pointer. The product accesses or uses a pointer that has not been initialized.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Common Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.ATPresentAttack requirements: A particular deployment or execution condition must be present.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.VCNoneVulnerable-system confidentiality: No direct loss is represented by this metric.VINoneVulnerable-system integrity: No direct loss is represented by this metric.VAHighVulnerable-system availability: A successful attack can cause a major loss.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SANoneSubsequent-system availability: No direct loss is represented by this metric.
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.
NetworkDenial of serviceCWE-824
A

Official authority intelligence

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

ENISA EUVD · EUVD-2026-108129Official EUVD mapping

libyang through 6.4.13 contains an uninitialized pointer free vulnerability in lydxml_env_netconf_rpc() in src/parser_xml.c when parsing NETCONF rpc action envelopes. Peers with a NETCONF session can send an action element containing non-whitespace text via lyd_parse_op() to crash servers like netopeer2 or corrupt the heap.

Official EUVD record ↗
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.
Fix availability varies by product
Affected
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
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
04

Evidence and provenance

Published 22 Oct 2026 · Last source change 22 Oct 2026, 10:57 UTC · CWE-824 · Access of Uninitialized Pointer

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 2026-10-23
European sourceENISA EUVD · EUVD-2026-108129
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD awaiting enrichment

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

Material change intelligence

What changed after publication

View recent updates ↗
  1. ENISA EUVD mappingEUVD-2026-108129 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2026-108129"}
    ENISA EUVD ↗
  2. Catalogue recordCVE added to the BlackTree catalogue.
    Official European vulnerability authority ↗
  3. Vendor guidanceAuthoritative vendor guidance changed: removed patch: github.com/927fce908774289a7d9c07fff5704c33965c9773; removed remediation: github.com/927fce908774289a7d9c07fff5704c33965c9773.
    Before
    patch: github.com/927fce908774289a7d9c07fff5704c33965c9773 · remediation: github.com/927fce908774289a7d9c07fff5704c33965c9773
    After
    no authoritative guidance recorded
    CNA ↗
  4. Affected versionsThe structured affected or fixed version information changed.
    Before
    libyang: ≤ 6.4.13 · 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.
    After
    libyang: ≤ 6.4.13 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
    CNA ↗
  5. Remediation statusRemediation status changed from Patch available to Awaiting fix.
    Before
    Patch available
    After
    Awaiting fix
    CNA ↗
  6. Vendor guidanceAuthoritative vendor guidance changed: added patch: github.com/927fce908774289a7d9c07fff5704c33965c9773; added remediation: github.com/927fce908774289a7d9c07fff5704c33965c9773; removed remediation: euvd.enisa.europa.eu/EUVD-2026-108129.
    Before
    remediation: euvd.enisa.europa.eu/EUVD-2026-108129
    After
    patch: github.com/927fce908774289a7d9c07fff5704c33965c9773 · remediation: github.com/927fce908774289a7d9c07fff5704c33965c9773
    github.com ↗
  7. Affected versionsThe structured affected or fixed version information changed.
    Before
    CESNET libyang 0 ≤6.4.13 · Fixed: No fixed version is explicitly recorded in the available ENISA EUVD evidence.
    After
    libyang: ≤ 6.4.13 · 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.
    CNA ↗
  8. Remediation statusRemediation status changed from Awaiting fix to Patch available.
    Before
    Awaiting fix
    After
    Patch available
    github.com ↗
  9. CVSS scoreCVSS scoring authority changed from Other authority to CNA; the displayed base score remained 6.0.
    Before
    6.0 (CVSS 4.0 · Other authority · CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N)
    After
    6.0 (CVSS 4.0 · CNA · CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N)
    CNA ↗
  10. Affected versionsThe structured affected or fixed version information changed.
    Before
    ENISA EUVD does not provide a structured affected-product range for this provisional report. · Fixed: No fixed version is explicitly recorded in the available ENISA EUVD evidence.
    After
    CESNET libyang 0 ≤6.4.13 · Fixed: No fixed version is explicitly recorded in the available ENISA EUVD evidence.
    Official European vulnerability authority ↗
  11. SeveritySeverity changed from Unknown to Medium.
    Before
    Unknown
    After
    Medium
    Other authority ↗
  12. CVSS scoreCVSS score changed from not recorded to 6.0 (CVSS 4.0 · Other authority · CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N).
    Before
    not recorded
    After
    6.0 (CVSS 4.0 · Other authority · CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N)
    Other authority ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
ENISA EUVD · EUVD-2026-108129↗Vendor CSAF · Red Hat Product Security↗CVE authority or vendor reference↗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-2026-115327 · cve.blacktree.nl