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CVE-2026-82438NVD status: Deferred

Apache Storm Webapp: Origin Validation Error

CVE-2026-82438 is a high-severity origin validation error vulnerability in Apache Storm Webapp from Apache, with a CVSS 3.1 base score of 8.1 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 Webapp to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.21% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

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

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache Storm Webapp3.0.0 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
NoneAvailability is not affected.

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

Official description

Description Three separate mechanisms allowed a web page on an unrelated origin to read responses that Storm's HTTP components served to an authenticated user. The Logviewer reflected the request's `Origin` header back in `Access-Control-Allow-Origin` while also sending `Access-Control-Allow-Credentials: true`. The published security model documents a permissive `Access-Control-Allow-Origin: *` posture as accepted, which is safe precisely because browsers refuse to honour `*` together with credentials; reflecting the concrete origin removes that protection. The shared CORS filter used by the UI, the Logviewer and DRPC was configured with a response header name where an initialisation parameter name was expected. The container ignored the setting and applied its own defaults, which allow credentials. Finally, the UI and Logviewer wrapped API responses in a caller-supplied JSONP callback for every GET request. A script element on any origin can load such a response, which bypasses the same-origin policy entirely rather than negotiating it, and there was no way to turn the behaviour off. In each case the effect is that a page visited by an authenticated operator can read cluster, topology and log data on their behalf. Mitigation Upgrade to 3.1.0, where the Logviewer no longer reflects the request origin in a credentialed response, the CORS filter is configured explicitly, and JSONP wrapping is governed by `ui.enable.jsonp`, which defaults to false. Note that disabling JSONP is a behaviour change for tooling that passes a `callback` query parameter; such tooling should be moved to ordinary JSON requests. Users who cannot upgrade immediately should place the UI, Logviewer and DRPC HTTP endpoints behind a reverse proxy that strips `Access-Control-Allow-Origin` and `Access-Control-Allow-Credentials` from responses and rejects requests carrying a `callback` parameter. 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: Origin Validation Error

The product does not properly verify that the source of data or communication is valid.

More Origin Validation Error vulnerabilities (CWE-346)

Timeline

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

References

Recent Origin Validation Error vulnerabilities

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