HighCVE-2019-5736

    The Linux Foundation runc: security vulnerability (CVE-2019-5736)

    Published Sources: CVE.org

    What is affected, what to do

    runc through 1.0-rc6, as used in Docker before 18.09.2 and other products, allows attackers to overwrite the host runc binary (and consequently obtain host root access) by leveraging the ability to execute a command as root within one of these types of containers: (1) a new container with an attacker-controlled image, or (2) an existing container, to which the attacker previously had write access, that can be attached with docker exec. This occurs because of file-descriptor mishandling, related to /proc/self/exe.

    An exploit is publicly available. Update Docker to version 18.09.2, Linux Containers LXC to version 3.2.0, Apache Mesos to version 1.4.3.

    Affected
    • Docker lt *..18.09.2
    • The Linux Foundation runc lte *..0.1.1
    • The Linux Foundation runc eq 1.0.0..1.0.0
    • Red Hat Container Development Kit eq 3.7..3.7
    • Redhat OpenShift eq 3.4..3.4
    • Redhat OpenShift eq 3.5..3.5
    • Redhat OpenShift eq 3.6..3.6
    • Redhat OpenShift eq 3.7..3.7
    • Redhat Enterprise Linux eq 8.0..8.0
    • Redhat Enterprise Linux Server eq 7.0..7.0
    • Linux Containers LXC lt *..3.2.0
    • Apache Mesos lt 1.4.0..1.4.3
    • Apache Mesos lt 1.5.0..1.5.3
    • Apache Mesos lt 1.6.0..1.6.2
    • Apache Mesos lt 1.7.0..1.7.2
    • OpenSUSE Backports SLE eq 15.0..15.0
    • openSUSE Leap eq 15.0..15.0
    • openSUSE Leap eq 15.1..15.1
    • openSUSE Leap eq 42.3..42.3
    • D2iQ Kubernetes Engine lt *..2.2.0-1.13.3
    • D2iQ DC/OS lt *..1.10.10
    • D2iQ DC/OS lt 1.10.11..1.11.9
    • D2iQ DC/OS lt 1.11.10..1.12.1
    • Fedora eq 29..29
    • Fedora eq 30..30
    • Canonical Ubuntu Linux eq 16.04..16.04
    • Canonical Ubuntu Linux eq 18.04..18.04
    • Canonical Ubuntu Linux eq 18.10..18.10
    • Canonical Ubuntu Linux eq 19.04..19.04
    • Micro Focus Service Management Automation eq 2018.02..2018.02
    • Micro Focus Service Management Automation eq 2018.05..2018.05
    • Micro Focus Service Management Automation eq 2018.08..2018.08
    • Micro Focus Service Management Automation eq 2018.11..2018.11
    Fixed in
    • Docker 18.09.2
    • Linux Containers LXC 3.2.0
    • Apache Mesos 1.4.3
    • Apache Mesos 1.5.3
    • Apache Mesos 1.6.2
    • Apache Mesos 1.7.2
    • D2iQ Kubernetes Engine 2.2.0-1.13.3
    • D2iQ DC/OS 1.10.10
    • D2iQ DC/OS 1.11.9
    • D2iQ DC/OS 1.12.1

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    8.6

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: NVD, CVSS v3

    8.6

    CVSS v3

    Severity High on the scale from 0 to 10.

    Source: CVE.org

    98.5 %

    EPSS score

    High — model estimates ≥ 50% chance of real-world exploitation within 30 days.

    Source: FIRST EPSS, percentile 99.92

    Show all metrics
    Severity
    High
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    122.87 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    PoC (publicly reported)
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    8.6 Methodology
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    8.6
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

    Read in glossary
    98.5 %
    High — model estimates ≥ 50% chance of real-world exploitation within 30 days.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    99.92
    Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    —
    Published

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    runc through 1.0-rc6, as used in Docker before 18.09.2 and other products, allows attackers to overwrite the host runc binary (and consequently obtain host root access) by leveraging the ability to execute a command as root within one of these types of containers: (1) a new container with an attacker-controlled image, or (2) an existing container, to which the attacker previously had write access, that can be attached with docker exec. This occurs because of file-descriptor mishandling, related to /proc/self/exe.

    Source: cvelistv5, NVD (NIST)

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    apachemesos
    • 1.6.0 – < 1.6.2
    • 1.5.0 – < 1.5.3
    • 1.4.0 – < 1.4.3
    • 1.7.0 – < 1.7.2
    • 1.6.2
    • 1.5.3
    • 1.4.3
    • 1.7.2
    d2iqkubernetes_engine
    • < 2.2.0-1.13.3
    • 2.2.0-1.13.3
    dockerdocker
    • < 18.09.2
    • 18.09.2
    googlekubernetes_engine
    • —
    • —
    hponesphere
    • —
    • —
    linuxcontainerslxc
    • < 3.2.0
    • 3.2.0
    linuxfoundationrunc
    • 1.0.0
    • ≤ 0.1.1
    • —
    • —
    microfocusservice_management_automation
    • 2018.05
    • 2018.11
    • 2018.08
    • 2018.02
    • —
    • —
    • —
    • —
    netapphci_management_node
    • —
    • —
    netappsolidfire
    • —
    • —
    opensusebackports_sle
    • 15.0
    • —
    redhatcontainer_development_kit
    • 3.7
    • —
    redhatopenshift
    • 3.5
    • 3.4
    • 3.6
    • 3.7
    • —
    • —
    • —
    • —

    Vendors and products

    Affected operating systems

    Affected operating systems
    Linuxredhatenterprise_linux8.0
    Linuxredhatenterprise_linux_server7.0
    Linuxopensuseleap15.0
    Linuxopensuseleap15.1
    Linuxopensuseleap42.3
    Linuxcanonicalubuntu_linux16.04
    Linuxcanonicalubuntu_linux18.04
    Linuxcanonicalubuntu_linux18.10
    Linuxcanonicalubuntu_linux19.04
    Otherd2iqdc\/os—
    Otherfedoraprojectfedora29
    Otherfedoraprojectfedora30

    Public exploit references

    Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

    Public exploit references
    GitHubFrichetten/CVE-2019-5736-PoC (opens in a new tab)github.comPoC (publicly reported)reported, not verified—
    GitHubq3k/cve-2019-5736-poc (opens in a new tab)github.comPoC (publicly reported)reported, not verified—
    Packet StormDocker Container Escape (opens in a new tab)packetstormsecurity.comPoC (publicly reported)reported, not verified—
    Packet StormDocker runc Command Execution Proof Of Concept (opens in a new tab)packetstormsecurity.comPoC (publicly reported)reported, not verified—
    Exploit-DBEDB-ID 46359 (opens in a new tab)exploit-db.comPoC (publicly reported)reported, not verified—
    Exploit-DBEDB-ID 46369 (opens in a new tab)exploit-db.comPoC (publicly reported)reported, not verified—

    References & sources

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