CyberSecBulletin
CVE-2026-82428NVD status: Deferred

Apache Storm Client: Improper Limitation of a Pathname to a Restricted Directory

CVE-2026-82428 is a high-severity improper limitation of a pathname to a restricted directory vulnerability in Apache Storm Client from Apache, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 3.1.0 as the first without the flaw, so updating Apache Storm Client to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.69% chance of exploitation within 30 days, higher than 53% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Apache Storm Client to 3.1.0 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache Storm Client3.0.0 up to, but not including, 3.1.03.1.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CISA (ADP).

Official description

Description Dependency artifacts uploaded with `storm jar --artifacts` were stored under a blob key derived only from the Maven coordinate, for example `dep---.jar`. The key was therefore identical for every user of the cluster and predictable in advance. When the blob already existed, the uploader caught `KeyAlreadyExistsException` and silently reused it, with no check that the existing blob's content or owner matched the artifact the submitter had resolved. A user who uploaded a blob under such a key first therefore controlled the bytes that every later submitter of the same coordinate would receive on the worker classpath, resulting in code execution inside another tenant's topology. This affects deployments where more than one principal may create blobs and where the `--artifacts` dependency feature is used. Mitigation Upgrade to 3.1.0, where each uploaded artifact receives a key carrying a freshly generated UUID and a pre-existing blob is no longer silently reused. Note that the corrected key generation is on the SUBMITTING CLIENT, so upgrading the cluster alone does not close this; every client that runs `storm jar --artifacts` must also be upgraded. Operators should audit existing `dep-` blobs for unexpected owners before upgrading. Users who cannot upgrade immediately should avoid the `--artifacts` mechanism in multi-tenant clusters and distribute dependencies inside the topology jar instead. Credit The ASF -- found using Claude agents to study the security of open-source projects, validated and reported by Apache Storm.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory

The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

How developers prevent this class of flaw

  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
  • Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.

More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).

References

Other vulnerabilities in Apache Storm Client

All Apache Storm Client vulnerabilities

Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities

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