Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessObtain Nomad job-submit/dispatch privileges
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DeliveryDeploy malicious workload to target client
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ExploitPlant symlink inside allocation directory
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ExecutionTrigger dispatch payload or executor log write
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PersistFollow symlink to overwrite host file outside allocation
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ImpactGain code execution as root on client host
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V5 - File Handling Symlink resolution safety
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| Exploitation Conditions | Exploitation requires the attacker to be able to run a workload on a Nomad client - specifically a parameterized/dispatch job that writes a dispatch payload, or any workload producing executor logs - and to place a symlink inside its own allocation directory that Nomad then follows during those writes. Escalation to code execution as root is conditioned on the Nomad client agent running as root on the host (a common deployment mode). Limiting factors: the attack vector is local (AV:L) - there is no remote unauthenticated path; the attacker needs low-level privileges to submit/dispatch a job (PR:L), so the realistic risk concentrates in multi-tenant clusters that accept jobs from untrusted submitters; impact beyond file modification (full root RCE) depends on the agent running as root rather than as an unprivileged user. |
| Impact | This is a credible operational priority but not an emergency. The vendor-supplied CVSS 3.1 vector (AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H, 8.4) describes a local, low-privilege, no-interaction flaw whose scope changes (S:C) because writes escape the allocation sandbox onto the host - consistent with the description. The vuln.today Decision label is 'this_week', which aligns with a serious-but-not-actively-exploited issue. There is no CISA KEV listing and no EPSS score in the input, so exploitation status is 'no public exploit identified at time of analysis'; do not treat this as in-the-wild. One internal conflict is worth flagging: the vendor vector sets C:N, yet the description explicitly states the flaw 'could lead to code execution as root on the client host,' which would normally imply high confidentiality impact as well - the published vector appears to score only the file-modification primitive, not the downstream root code-execution path, so the real worst-case impact is likely higher than 8.4 suggests. The AV:L vector also means this is not remotely reachable by an unauthenticated internet attacker; the adversary must already be able to run a workload on a Nomad client, so the practical risk is highest in multi-tenant Nomad clusters where untrusted job submitters exist. |
| Exploit ScenarioDerived | An attacker who can submit or dispatch jobs to a Nomad cluster schedules a malicious workload on a client and plants a symlink inside its allocation directory. When Nomad writes the dispatch payload or executor logs, it follows the symlink and writes to an attacker-chosen path outside the allocation; if the client agent runs as root, this file overwrite is leveraged into code execution as root on the client host. No public exploit code is identified at time of analysis, and user interaction is not required (UI:N). |
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Alert meAnalysisAIv1 – Oct 29, 2026
Symlink following during dispatch payload and executor log writes in HashiCorp Nomad and Nomad Enterprise lets a malicious workload redirect those writes outside its own allocation directory and modify arbitrary files on the client host; when the Nomad client agent runs as root, that file-write primitive can be escalated to code execution as root. The flaw is local and requires an authenticated position with low privileges - the ability to submit or dispatch a job on the client - so realistic exposure concentrates in multi-tenant clusters that accept jobs from untrusted submitters, and full root compromise depends on the agent running as root (a common deployment mode). Fixed versions are Nomad 2.1.0 and Nomad Enterprise 2.1.0, 1.11.12, and 1.10.18; no public exploit code was identified at time of analysis and the issue is not in CISA KEV, which places it in a this-week operational priority band rather than an emergency.
RemediationAI
Upgrade to a fixed release as the complete fix: Nomad 2.1.0 for the open-source edition, and Nomad Enterprise 2.1.0, 1.11.12, or 1.10.18 depending on the branch in use - patch the client agents, since the vulnerable write paths (dispatch payload and executor log handling) execute on the client host, and confirm agents actually restart onto the new binary. See the vendor advisory HCSEC-2026-52 at https://discuss.hashicorp.com/t/hcsec-2026-52-nomad-dispatch-payload-writes-can-escape-the-allocation-directory-through-symlinks/77930 for the authoritative version matrix; no documented vendor workaround is included in the available data, and the advisory frames updating as the fix. Where immediate upgrade is not possible, reduce exposure along the two limiting factors identified in the assessment: stop running the Nomad client agent as root so that a successful symlink-following write cannot translate into root-level code execution, at the cost of losing agent capabilities that require root (privileged drivers, root-owned host volumes, some networking setups); and tighten ACLs so only trusted submitters can create parameterized/dispatch jobs or run workloads that generate executor logs, which shrinks the attacker population but reduces the self-service flexibility of multi-tenant clusters. Neither measure removes the underlying link-following flaw, so both are temporary compensations until the agent is on a fixed version.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 2 packages in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The root cause is CWE-59 (Improper Link Resolution Before File Access), often called link following: the Nomad client agent composes paths for dispatch payload files and executor logs inside a workload's allocation directory and opens them for writing without ensuring that no component of the path is a symlink planted by the workload itself. Because the allocation directory is writable by the job, a malicious workload can substitute a symlink for the intended file or directory component and cause the agent to write attacker-influenced content to a location chosen by the attacker. The CVSS vector (AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H) confirms a local attack vector, low privileges, no user interaction, and a scope change - the vulnerable component's privileges are used against a resource outside its security scope, i.e. the host filesystem rather than the allocation sandbox. Integrity and availability impacts are high while confidentiality is not directly implicated by the write primitive as scored; the independent assessment additionally rates confidentiality high because a successful root-level write can be leveraged toward code execution. Escalation from file modification to root code execution is conditioned on the client agent being run as root, which is a documented common deployment mode; the specific files and payload contents used to achieve execution are not described in the available sources.
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Severity by source
AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H
Local because the attacker must run a workload on the client (AV:L), PR:L for job-submit rights, S:C as writes escape the allocation to the host, and C:H added to reflect the stated root code-execution outcome.
Primary rating from Vendor (HashiCorp).
CVSS VectorVendor: HashiCorp
Lifecycle Timeline
2DescriptionCVE.org
HashiCorp Nomad and Nomad Enterprise are vulnerable to symlink following during dispatch payload and executor log writes that may allow a malicious workload to modify files outside its allocation directory. When the client agent runs as root, this could lead to code execution as root on the client host. This vulnerability (CVE-2026-107347) is fixed in Nomad 2.1.0 and Nomad Enterprise 2.1.0, 1.11.12, and 1.10.18.
Articles & Coverage 2
Executive ViewAI
HashiCorp Nomad and Nomad Enterprise are affected by a high-severity vulnerability that allows a low-privileged, authenticated user to write arbitrary files on client hosts, potentially leading to root code execution when the agent runs as root. Organizations running multi-tenant Nomad clusters where untrusted parties can submit jobs face elevated risk of host compromise, which could impact data integrity and service availability across the environment.
No vendor-released patch identified at time of analysis. As interim mitigations, restrict job submission privileges to trusted users, avoid running Nomad client agents as root, implement file system monitoring to detect unauthorized writes, and isolate multi-tenant clusters to limit lateral movement.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Remote Code Execution represents the critical moment when an attacker successfully runs arbitrary code on a target system without physical access.
HashiCorp Nomad and Nomad Enterprise versions 1.5.0 up to 1.5.2 allow unauthenticated users to bypass intended ACL autho
HashiCorp Nomad and Nomad Enterprise version 0.2.0 up to 1.3.0 were impacted by go-getter vulnerabilities enabling privi
HashiCorp Nomad and Nomad Enterprise up to 0.10.2 incorrectly validated role/region associated with TLS certificates use
HashiCorp Nomad 0.9.0 through 0.9.1 has Incorrect Access Control via the exec driver. Rated critical severity (CVSS 9.8)
HashiCorp Nomad and Nomad Enterprise version 0.9.0 up to 0.12.5 client file sandbox feature can be subverted using eithe
Symlink following during same-client allocation data migration in HashiCorp Nomad and Nomad Enterprise allows a workload
Authenticated code execution on Nomad client hosts is possible in HashiCorp Nomad and Nomad Enterprise 1.10.0 through ve
HashiCorp Nomad and Nomad Enterprise 1.5.0 allow a job submitter to escalate to management-level privileges using worklo
HashiCorp Nomad and Nomad Enterprise up to 1.0.13, 1.1.7, and 1.2.0, with the QEMU task driver enabled, allowed authenti
HashiCorp Nomad and Nomad Enterprise Raft RPC layer allows non-server agents with a valid certificate signed by the same
HashiCorp Nomad and Nomad Enterprise 1.6.12 up to 1.7.9, and 1.8.1 archive unpacking during migration is vulnerable to p
CVE-2025-4922 is a security vulnerability (CVSS 8.1). High severity vulnerability requiring prompt remediation.
EUVD-2026-113318
GHSA-qx6c-5f28-88p2
NVD
CVE.org
EPSS
Vulnrichment
Exploit-DB