CriticalCVE-2015-1427

    Elasticsearch Groovy Scripting Engine Remote Code Execution Vulnerability (CVE-2015-1427)

    Published In CISA KEV since Sources: CVE.org, OSV

    What is affected, what to do

    The Groovy scripting engine in Elasticsearch before 1.3.8 and 1.4.x before 1.4.3 allows remote attackers to bypass the sandbox protection mechanism and execute arbitrary shell commands via a crafted script.

    The vulnerability is being actively exploited; treat it as a priority. Update Elasticsearch to version 1.3.8, Elasticsearch to version 1.4.3. Immediate actions, mitigation and detection rules are in the runbook below.

    Affected
    • Elasticsearch lt *..1.3.8
    • Elasticsearch lt 1.4.0..1.4.3
    • Red Hat Fuse 7 eq 1.0.0..1.0.0
    Fixed in
    • Elasticsearch 1.3.8
    • Elasticsearch 1.4.3

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

    Metrics

    9.8

    Priority

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

    Source: NVD, CVSS v3

    9.8

    CVSS v3

    Severity Critical on the scale from 0 to 10.

    Source: CVE.org, OSV

    99.91 %

    EPSS score

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

    Source: FIRST EPSS, percentile 99.97

    Show all metrics
    Severity
    Critical
    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
    228.95 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
    actively exploited
    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
    9.8 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
    9.8
    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
    99.91 %
    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
    99.97
    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
    Actively exploited
    Published
    In CISA KEV since

    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

    Response and mitigation

    Why act now?

    Prioritisation rationale

    This CVE is on KEV because it enables unauthenticated remote code execution through a single HTTP POST and has been weaponised for years in mass-scanning campaigns (cryptominers, IoT botnets, initial access for data theft); exploitation likelihood sits among the highest in the entire KEV catalogue. The CVSS vector AV:N/AC:L/PR:N/UI:N means any network-reachable Elasticsearch 1.3.x/1.4.x node is effectively already compromisable — no credentials, no user interaction. Treat as P1 whenever an affected node is internet-exposed or lives in a DMZ; P2 for internal-only nodes, but only if lateral-movement paths to crown jewels can be ruled out (Elasticsearch frequently indexes logs that contain credentials, customer data and tokens). For NIS2-regulated organisations: validate incident-reporting obligations the moment exploitation traces appear in logs.

    1. Runbook step 1

      Immediate response (0-24 h)

      • Upgrade every Elasticsearch instance to at least 1.3.8 or 1.4.3, or better to a currently supported 2.x/5.x/6.x/7.x/8.x line. Legacy clusters that cannot be patched must be taken off the network until replaced.
      • Disable dynamic scripting immediately: set script.disable_dynamic: true in elasticsearch.yml and restart the node. This closes the Groovy sandbox-escape path completely.
      • Firewall/security-group HTTP transport (TCP/9200) and node transport (TCP/9300) to permit only known application backends and admin jump hosts; drop all internet, DMZ and office-VLAN access by default.
      • Hunt for prior compromise: correlate _search requests containing script_fields, lang=groovy or java.lang.Runtime in reverse-proxy and load-balancer logs for the last 90 days. On any hit, treat the node as compromised — memory capture, forensics, rotate credentials for every datastore and cloud API the service could reach.
      • Audit the Elasticsearch service account: if it runs as root or has write access to ~/.ssh, cron.d or systemd units, move it to a dedicated unprivileged user and inspect persistence locations (crontab, authorized_keys, systemd timers).

    2. Runbook step 2

      Mitigation layers

      • Network segmentation: place Elasticsearch nodes in a dedicated backend VLAN; inbound only 9200/9300 from defined sources, outbound no internet reachability at all (blocks second-stage payload fetching via Runtime.exec("curl ...")).
      • Reverse proxy with authentication in front of every cluster (nginx with Basic/mTLS, Shield/X-Pack, Search Guard); inspect POST bodies on /_search, /*/_search, /_msearch.
      • WAF/IPS rule: block request bodies matching "lang"\s*:\s*"groovy", java.lang.Math.class.forName, Runtime.getRuntime, ProcessBuilder — ModSecurity custom rule or Suricata Lua script.
      • Host hardening: constrain the Elasticsearch user via systemd (NoNewPrivileges=yes, ProtectSystem=strict, ProtectHome=yes, PrivateTmp=yes) and deploy an AppArmor/SELinux profile that denies execve to shell binaries.
      • Egress filtering on the node: nftables/iptables rules dropping outbound 80/443/4444/8080 to anything not whitelisted, to kill reverse shells and miner downloads.
      • Supply-chain scan: remove Maven artefacts org.elasticsearch:elasticsearch 0.12.x-0.14.x and Red Hat Fuse 1.0.0 from internal Nexus/Artifactory repos, verify transitive dependencies in build pipelines.

    3. Runbook step 3

      Detection rules

      • Zeek/Suricata HTTP log: http.request.body contains "lang":"groovy" or java.lang.Runtime targeting port 9200 hosts — Sigma detection: selection: http.uri|contains: '_search' and http.request_body|contains: 'groovy'.
      • EDR/Sysmon EID 1 (ProcessCreate): parent java (Elasticsearch JVM) spawning sh, bash, curl, wget, nc, python, powershell — the clearest signal of a successful sandbox escape. KQL: DeviceProcessEvents | where InitiatingProcessFileName == "java" and FileName in ("sh","bash","curl","wget","nc").
      • Linux auditd: execve syscall whose ppid belongs to the Elasticsearch service and whose exe is outside /usr/lib/jvm/* — audit rule -a always,exit -F arch=b64 -S execve -F uid=elasticsearch.
      • Reverse-proxy access-log pattern: HTTP 200 on POST /_search with unusually large body (>2 KB) from single source IPs at tight cadence; alert on baseline deviation.
      • Netflow / Zeek conn.log: outbound connections from the Elasticsearch host to external IPs on anything other than 9200/9300 — in healthy clusters this is essentially never legitimate.

    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
    Actively exploited: treat the vulnerability as a priority in vulnerability handling under Art. 21(2)(e) NIS2. If it is exploited in your environment, check the reporting obligation under Art. 23 (early warning within 24 hours).
    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
    Since 11.09.2026, manufacturers of affected products with digital elements must report actively exploited vulnerabilities under Art. 14 CRA, with an early warning within 24 hours via ENISA's single reporting platform.
    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

    The Groovy scripting engine in Elasticsearch before 1.3.8 and 1.4.x before 1.4.3 allows remote attackers to bypass the sandbox protection mechanism and execute arbitrary shell commands via a crafted script.

    Source: NVD (NIST), OSV (Open Source Vulnerabilities), cvelistv5, CISA KEV Catalog, CVE.org (MITRE)

    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
    elasticelasticsearch
    • < 1.3.8
    • 1.4.0 – < 1.4.3
    • 1.3.8
    • 1.4.3
    redhatfuse
    • 1.0.0
    • —
    mavenorg.elasticsearch:elasticsearch
    • 0.18.7
    • 1.0.0.RC1
    • 1.2.0
    • 0.90.3
    • 0.19.5
    • 0.19.0
    • 0.17.2
    • 0.8.0
    • 0.17.6
    • 0.90.0.Beta1
    • 0.19.12
    • 0.18.4
    • 0.17.8
    • 0.16.4
    • 1.4.2
    • 0.15.0
    • 1.3.3
    • 0.19.1
    • 0.20.4
    • 0.14.4
    • 0.20.1
    • 0.90.12
    • 1.1.0
    • 0.19.9
    • 1.3.2
    • 0.18.6
    • 1.0.1
    • 0.15.1
    • 1.0.0.Beta2
    • 0.13.0
    • 0.11.0
    • 0.90.10
    • 0.7.1
    • 0.6.0
    • 0.19.3
    • 1.3.7
    • 0.19.7
    • 0.19.0.RC3
    • 0.15.2
    • 0.16.1
    • 0.90.9
    • 1.2.4
    • 1.1.2
    • 1.3.6
    • 1.4.0
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —
    • —

    Vendors and products

    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
    CISA KEV CatalogCISA Known Exploited Vulnerability (opens in a new tab)cisa.govactively exploited
    Packet StormElasticsearch 1.3.7 1.4.2 Sandbox Escape Command Execution (opens in a new tab)packetstormsecurity.comPoC (publicly reported)reported, not verified—
    Packet StormElasticSearch Unauthenticated Remote Code Execution (opens in a new tab)packetstormsecurity.comPoC (publicly reported)reported, not verified—
    PoC-in-GitHub (nomi-sec)vulhub-elasticsearch-cve-2015-1427 (opens in a new tab)github.comPoC (publicly reported)reported, not verified

    References & sources

    • NVD (NIST)vuln/detail/CVE-2015-1427advisory
    • access.redhat.comRHSA-2017:0868web, Vendor advisory, x_refsource_REDHAT, Third-party advisory
    • exchange.xforce.ibmcloud.comelasticsearch-cve20151427-command-exec(100850)web, Vulnerability database, x_refsource_XF, Third-party advisory, Vulnerability database
    • elastic.cocommunity/securityweb
    • packetstormsecurity.comfiles/130368/Elasticsearch-1.3.7-1.4.2-Sandbox-Escape-Command-E…web, x_refsource_MISC, Third-party advisory, Vulnerability database
    • packetstormsecurity.comfiles/130784/ElasticSearch-Unauthenticated-Remote-Code-Executio…web, x_refsource_MISC, Exploit, Third-party advisory, Vulnerability database
    • elasticsearch.comblog/elasticsearch-1-4-3-1-3-8-releasedweb
    • securityfocus.com20150211 Elasticsearch vulnerability CVE-2015-1427Mailing list, x_refsource_BUGTRAQ, Broken link, Third-party advisory, Vulnerability database
    • securityfocus.com72585Vulnerability database, x_refsource_BID, Broken link, Third-party advisory, Vulnerability database
    • elasticsearch.comblog/elasticsearch-1-4-3-1-3-8-releasedx_refsource_CONFIRM, Patch, Vendor advisory
    • elastic.cocommunity/securityx_refsource_CONFIRM, Not applicable, Vendor advisory
    • cisa.govknown-exploited-vulnerabilities-catalog?field_cve=CVE-2015-1427government-resource, US government resource
    Embed badge

    Show the severity and KEV status of this vulnerability on your site – with a link back here. The image is updated hourly.

    Badge preview for CVE-2015-1427
    <a href="https://intel.neosec.eu/en/cve/CVE-2015-1427"><img src="https://intel.neosec.eu/badge/cve/CVE-2015-1427.svg?lang=en" alt="CVE-2015-1427 – NEOSEC Intel" height="20"></a>