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CVE-2026-120307

Beta9 container escape via unvalidated sandbox file paths

CVSS score

9.9

EPSS probability

—

Risk score

1.0

Published

3 h ago

Official patch verified

Etkilenen ürün ve sürüm için yayımlanan güvenlik güncellemesini uygulayın.

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Vulnerability description

DayBreach AI Explanation

Verified against sources

CVE-2026-120307 Container Escape Vulnerability in Beta9 Worker

Sources read

1

Source agreement

Tam uyum

Evidence confidence

%55

Short explanation

The Beta9 worker contains a container escape vulnerability due to unvalidated sandbox file paths. This flaw allows a low-privileged tenant to perform file operations with root permissions on the host worker machine. The issue is fixed in worker 0.1.756.

Why does it matter?

An authenticated tenant can read, write, or delete files on the host worker machine, leading to unauthorized access to other tenants' data and potential compromise of Kubernetes cluster-admin privileges.

What should be done?

  • Update the Beta9 worker to version 0.1.756 or later
  • Follow vendor advisories and patch recommendations
Chain of evidence and sources3 verified claims

Beta9 worker, doğrulanmamış sandbox dosya yolları nedeniyle bir konteyner dışına çıkma zafiyeti içermektedir.

Bir kiracı, ana işçi makinesi üzerinde root yetkileri ile dosya okuyabilir, yazabilir ve silebilir.

Zafiyet worker 0.1.756 sürümünde giderilmiştir.

Show the technical text from the sources

The Beta9 worker serves the sandbox file API from outside the container. getHostPathFromContainerPath turns the tenant's container path into a worker path. If the unresolved path starts with a mount destination, including the default upload mount at /tmp/.beta9, the remainder is joined onto that mount's source with filepath.Join, which cleans parent-directory segments after the prefix check. A long enough run of those segments names any absolute path on the worker. A path that matches no mount is joined onto the container root and opened in the worker's own filesystem, so an absolute symbolic link such as /var/run pointing at /run is followed against the worker root. Upload, download, stat, list, find-in-files, replace-in-files, and delete-file all call this helper. A tenant with a workspace token and one running sandbox can read, write, list, and delete files on the hosting worker as root, including files of other tenants on that machine. A read-only proof downloaded the worker pod's Kubernetes service account token through the file API for a path that did not exist inside the sandbox. In the shipped remote-node manifests that service account is bound to cluster-admin. Fixed in worker 0.1.756: sandbox file operations and workspace sync open paths with os.OpenRoot, so parent-directory and symlink lookups stay inside the container root or the mount source.

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CWE: CWE-22, CWE-23, CWE-59

This explanation was compiled automatically from the source records. Scores, active exploitation, patch and exploit status come straight from the sources.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-120307 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1beam-cloudBeta9 worker View
Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
9.9CVSS V31CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HNVD
9.9CVSS V3_1CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HCVE CNA

Patch and Remediation Guide

Solution & Remediation Advisory

Patch verified

4 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

cvelist

Handle sandbox edge cases (fix pull request)

Open source
cvelist

Fix commit a28bf12

Open source
reference

Handle sandbox edge cases (fix pull request)

Open source
reference

Fix commit a28bf12

Open source
Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Apply the official update named in the evidence only to the matching product and version.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-120307 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-120307 weaknesses.

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsLow
UserGerekmiyor

Official Sources and Advisories

CVSS Vector Radar Chart

9.9 / 10
Attack VectorNetworkComplexityLowPrivilegesLowUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow privileges
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)High

Yama doğrulandı

4 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

Follow the vendor

Weakness Type (CWE & CAPEC)

Similar Vulnerabilities

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