BlackTreeCVE Intelligence
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Full vulnerability report · 2026
CVE-2026-3731High confidence

libssh SFTP Extension Name sftp.c sftp_extensions_get_data out-of-bounds

Unknown · libssh

6.9MediumCVSS 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 1 structured product or package state 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.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 1.20% 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 Unknown libssh 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 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

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

5 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 1 affected package state 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 · sourcelibsshVendor fix publishedDebian records a fixed source-package version for this release.0.11.5-0+deb13u1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcelibsshAffected, no fix publishedDebian currently tracks this release as open.Not published in this feedDebian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcelibsshVendor fix publishedDebian records a fixed source-package version for this release.0.12.0-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcelibsshVendor fix publishedDebian records a fixed source-package version for this release.0.12.0-1Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelibsshVendor fix publishedCanonical reports that a fixed source package version has been published. Repository candidate availability is not checked by BlackTree.0.10.6-2ubuntu0.4Canonical Ubuntu Security ↗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-2026-3731 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitylibssh: libssh: Denial of Service via out-of-bounds read in SFTP extension name handler
22 known affected

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

  • libssh as a component of Red Hat Enterprise Linux 10
  • libssh-config as a component of Red Hat Enterprise Linux 10
  • libssh-devel as a component of Red Hat Enterprise Linux 10
  • libssh.src as a component of Red Hat Enterprise Linux 10
  • libssh2 as a component of Red Hat Enterprise Linux 6
  • libssh2-devel as a component of Red Hat Enterprise Linux 6
  • libssh2-docs as a component of Red Hat Enterprise Linux 6
  • libssh2.src as a component of Red Hat Enterprise Linux 6
  • libssh2 as a component of Red Hat Enterprise Linux 7
  • libssh2-devel as a component of Red Hat Enterprise Linux 7
  • libssh2-docs as a component of Red Hat Enterprise Linux 7
  • libssh2.src as a component of Red Hat Enterprise Linux 7
Summary
A flaw was found in libssh. A remote attacker could trigger an out-of-bounds read vulnerability in the SFTP Extension Name Handler by manipulating the `idx` argument in the `sftp_extensions_get_name` or `sftp_extensions_get_data` functions. This could lead to a Denial of Service (DoS), making the affected system unresponsive.
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-2026-10234

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

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
Not supplied in the stored EUVD record
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 1 structured product or package state remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

A weakness has been identified in libssh up to 0.11.3. The impacted element is the function sftp_extensions_get_name/sftp_extensions_get_data of the file src/sftp.c of the component SFTP Extension Name Handler. Executing a manipulation of the argument idx can lead to out-of-bounds read. The attack may be performed from remote. Upgrading to version 0.11.4 and 0.12.0 is sufficient to resolve this issue. This patch is called 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60. You should upgrade the affected component.

What

A weakness has been identified in libssh up to 0.11.3. The impacted element is the function sftp_extensions_get_name/sftp_extensions_get_data of the file src/sftp.c of the component SFTP Extension Name Handler. Executing a manipulation of the argument idx can lead to out-of-bounds read. The attack may be performed from remote. Upgrading to version 0.11.4 and 0.12.0 is sufficient to resolve this issue. This patch is called 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60. You should upgrade the affected component.

Why

The product reads data past the end, or before the beginning, of the intended buffer.

How

An attacker operating through a network path 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 weakness has been identified in libssh up to 0.11.3. The impacted element is the function sftp_extensions_get_name/sftp_extensions_get_data of the file src/sftp.c of the component SFTP Extension Name Handler. Executing a manipulation of the argument idx can lead to out-of-bounds read. The attack may be performed from remote. Upgrading to version 0.11.4 and 0.12.0 is sufficient to resolve this issue. This patch is called 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60. You should upgrade the affected component.

Why

The product reads data past the end, or before the beginning, of the intended buffer.

How

An attacker operating through a network path 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
a network path → Out-of-bounds Read → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Not a CVSS 4.0 base metric
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-125 ↗

CWE-125: Out-of-bounds Read. The product reads data past the end, or before the beginning, of the intended buffer.

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:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X

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.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.ATNoneAttack requirements: No additional deployment or execution condition is required.PRNonePrivileges required: The attacker does not need an account or existing 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.VALowVulnerable-system availability: A successful attack can cause a limited 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.
NetworkUnauthenticatedCWE-125
A

Official authority intelligence

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

BSI · German · WID-SEC-2026-1007IBM App Connect Enterprise: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in IBM App Connect Enterprise ausnutzen, um Sicherheitsvorkehrungen zu umgehen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen, um einen SQL-Injection Angriff durchzuführen, und um beliebigen Programmcode auszuführen.

Official advisory ↗
BSI · German · WID-SEC-2026-0634libssh: Schwachstelle ermöglicht Denial of Service

Ein entfernter, anonymer Angreifer kann eine Schwachstelle in libssh ausnutzen, um einen Denial of Service Angriff durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20260311Security Bulletin 11 Mar 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 11 Mar 2026, published on 11 March 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0627Multiples vulnérabilités dans les produits Splunk

ve.org/CVERecord?id=CVE-2026-3538 Référence CVE CVE-2026-3539 https://www.cve.org/CVERecord?id=CVE-2026-3539 Référence CVE CVE-2026-3540 https://www.cve.org/CVERecord?id=CVE-2026-3540 Référence CVE CVE-2026-3541 https://www.cve.org/CVERecord?id=CVE-2026-3541 Référence CVE CVE-2026-3542 https://www.cve.org/CVERecord?id=CVE-2026-3542 Référence CVE CVE-2026-3543 https://www.cve.org/CVERecord?id=CVE-2026-3543 Référence CVE CVE-2026-3544 https://www.cve.org/CVERecord?id=CVE-2026-3544 Référence CVE CVE-2026-3545 https://www.cve.org/CVERecord?id=CVE-2026-3545 Référence CVE CVE-2026-35469 https://www.cve.org/CVERecord?id=CVE-2026-35469 Référence CVE CVE-2026-3731 https://www.cve.org/CVERecord?id=CVE-2026-3731 Référence CVE CVE-2026-39892 https://www.cve.org/CVERecord?id=CVE-2026-39892 Référence CVE CVE-2026-40175 https://www.cve.org/CVERecord?id=CVE-2026-40175 Référence CVE CVE-2026-40192 https://www.cve.org/CVERecord?id=CVE-2026-40192 Référence CVE CVE-2026-40200 https://www.cve.org/CVERecord?id=CVE-2026-40200 Référence CVE CVE-2026-4111 https://www.cve.org/CVERecord?id=CVE-2026-4111 Référence CVE CVE-2026-41324 https://www.cve.org/CVERecord?id=CVE-2026-41324 Référence CVE CVE-2026-42308 https://www.cve.org/CVERecord?id=CVE-2026-42308 Référence CVE CVE-2026-42309 https://www.cve.org/CVERecord?id=CVE

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0334Vulnérabilité dans les produits Microsoft

Une vulnérabilité a été découverte dans les produits Microsoft. Elle permet à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0326Multiples vulnérabilités dans les produits VMware

g/CVERecord?id=CVE-2026-29786 Référence CVE CVE-2026-31802 https://www.cve.org/CVERecord?id=CVE-2026-31802 Référence CVE CVE-2026-3195 https://www.cve.org/CVERecord?id=CVE-2026-3195 Référence CVE CVE-2026-3196 https://www.cve.org/CVERecord?id=CVE-2026-3196 Référence CVE CVE-2026-32249 https://www.cve.org/CVERecord?id=CVE-2026-32249 Référence CVE CVE-2026-32597 https://www.cve.org/CVERecord?id=CVE-2026-32597 Référence CVE CVE-2026-3441 https://www.cve.org/CVERecord?id=CVE-2026-3441 Référence CVE CVE-2026-3442 https://www.cve.org/CVERecord?id=CVE-2026-3442 Référence CVE CVE-2026-3497 https://www.cve.org/CVERecord?id=CVE-2026-3497 Référence CVE CVE-2026-3731 https://www.cve.org/CVERecord?id=CVE-2026-3731 Référence CVE CVE-2026-3783 https://www.cve.org/CVERecord?id=CVE-2026-3783 Référence CVE CVE-2026-3784 https://www.cve.org/CVERecord?id=CVE-2026-3784 Gestion détaillée du document le 20 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 france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la Défense et de la Sécurité Nationale / Agence nationale de la sécurité des systèmes d'information

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-0316Multiples vulnérabilités dans les produits VMware

g/CVERecord?id=CVE-2026-29786 Référence CVE CVE-2026-31802 https://www.cve.org/CVERecord?id=CVE-2026-31802 Référence CVE CVE-2026-3195 https://www.cve.org/CVERecord?id=CVE-2026-3195 Référence CVE CVE-2026-3196 https://www.cve.org/CVERecord?id=CVE-2026-3196 Référence CVE CVE-2026-32249 https://www.cve.org/CVERecord?id=CVE-2026-32249 Référence CVE CVE-2026-32597 https://www.cve.org/CVERecord?id=CVE-2026-32597 Référence CVE CVE-2026-3441 https://www.cve.org/CVERecord?id=CVE-2026-3441 Référence CVE CVE-2026-3442 https://www.cve.org/CVERecord?id=CVE-2026-3442 Référence CVE CVE-2026-3497 https://www.cve.org/CVERecord?id=CVE-2026-3497 Référence CVE CVE-2026-3731 https://www.cve.org/CVERecord?id=CVE-2026-3731 Référence CVE CVE-2026-3783 https://www.cve.org/CVERecord?id=CVE-2026-3783 Référence CVE CVE-2026-3784 https://www.cve.org/CVERecord?id=CVE-2026-3784 Gestion détaillée du document le 19 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 france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la Défense et de la Sécurité Nationale / Agence nationale de la sécurité des systèmes d'information

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2026-006646libsshにおける複数の脆弱性

libssh バージョン 0.11.3 までに弱点が特定されています。影響を受ける要素は、コンポーネント SFTP Extension Name Handler のファイル src/sftp.c 内の関数 sftp_extensions_get_name および sftp_extensions_get_data です。引数 idx を操作すると、境界外読み取りが発生する可能性があります。この攻撃はリモートから実行される可能性があります。この問題を解決するには、バージョン 0.11.4 および 0.12.0 へのアップグレードが必要です。このパッチは 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60 と呼ばれています。影響を受けるコンポーネントをアップグレードしてください。

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.
Fix availability varies by product
Affected
Fixed
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
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 8 Mar 2026 · Last source change 11 Mar 2026, 19:50 UTC · CWE-125 · Out-of-bounds Read

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-2026-10234
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD enriched

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    libssh as a component of Red Hat Enterprise Linux 10; libssh-config as a component of Red Hat Enterprise Linux 10; libssh-devel as a component of Red Hat Enterprise Linux 10; libssh.src as a component of Red Hat Enterprise Linux 10; libssh2 as a component of Red Hat Enterprise Linux 6; libssh2-devel as a component of Red Hat Enterprise Linux 6; libssh2-docs as a component of Red Hat Enterprise Linux 6; libssh2.src as a component of Red Hat Enterprise Linux 6; libssh2 as a component of Red Hat Enterprise Linux 7; libssh2-devel as a component of Red Hat Enterprise Linux 7; libssh2-docs as a component of Red Hat Enterprise Linux 7; libssh2.src as a component of Red Hat Enterprise Linux 7; libssh as a component of Red Hat Enterprise Linux 8; libssh-config as a component of Red Hat Enterprise Linux 8; libssh-devel as a component of Red Hat Enterprise Linux 8; libssh.src as a component of Red Hat Enterprise Linux 8; libssh as a component of Red Hat Enterprise Linux 9; libssh-config as a component of Red Hat Enterprise Linux 9; libssh-devel as a component of Red Hat Enterprise Linux 9; libssh.src as a component of Red Hat Enterprise Linux 9; openshift/ose-rhel-coreos-9 as a component of Red Hat OpenShift Container Platform 4 · Fixed: libssh-main@aarch64 as a component of Red Hat Hardened Images; libssh-main@noarch as a component of Red Hat Hardened Images; libssh-main@src as a component of Red Hat Hardened Images; libssh-main@x86_64 as a component of Red Hat Hardened Images
    After
    libssh as a component of Red Hat Enterprise Linux 10; libssh-config as a component of Red Hat Enterprise Linux 10; libssh-devel as a component of Red Hat Enterprise Linux 10; libssh.src as a component of Red Hat Enterprise Linux 10; libssh2 as a component of Red Hat Enterprise Linux 6; libssh2-devel as a component of Red Hat Enterprise Linux 6; libssh2-docs as a component of Red Hat Enterprise Linux 6; libssh2.src as a component of Red Hat Enterprise Linux 6; libssh2 as a component of Red Hat Enterprise Linux 7; libssh2-devel as a component of Red Hat Enterprise Linux 7; libssh2-docs as a component of Red Hat Enterprise Linux 7; libssh2.src as a component of Red Hat Enterprise Linux 7; libssh as a component of Red Hat Enterprise Linux 8; libssh-config as a component of Red Hat Enterprise Linux 8; libssh-devel as a component of Red Hat Enterprise Linux 8; libssh.src as a component of Red Hat Enterprise Linux 8; libssh as a component of Red Hat Enterprise Linux 9; libssh-config as a component of Red Hat Enterprise Linux 9; libssh-devel as a component of Red Hat Enterprise Linux 9; libssh.src as a component of Red Hat Enterprise Linux 9; 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: libssh-main@aarch64 as a component of Red Hat Hardened Images; libssh-main@noarch as a component of Red Hat Hardened Images; libssh-main@src as a component of Red Hat Hardened Images; libssh-main@x86_64 as a component of Red Hat Hardened Images
    Red Hat Product Security ↗
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-2026-10234↗Vendor CSAF · Red Hat Product Security↗Patch or update reference↗Patch or update reference↗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-2026-3731 · cve.blacktree.nl