Live Exposure Defense: From CVE to Confirmed Exposure in 12 Hours – See more

Back
New CVE Detected

CVE-2026-78329 – WebSocket Header Injection / Filter Bypass – Apache Camel camel-undertow 4.11.0–4.2

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-78329 is an improper input validation vulnerability (CWE-20) in the camel-undertow component of Apache Camel. The UndertowEndpoint class overwrote its Undertow-specific header filter strategy with the generic HTTP one, so undertow-specific header filtering never ran on endpoint-configured routes. This lets an attacker inject legacy websocket.* prefixed headers that are read by a downstream Undertow WebSocket producer as dispatch directives, allowing messages to be delivered to a peer other than the one the route intended, and lets header names Undertow itself rejects pass through onto the Exchange instead of being dropped.

Technical details

  • Root cause: UndertowEndpoint defaulted its headerFilterStrategy field to the base HttpHeaderFilterStrategy and pushed that instance into the lazily-created UndertowHttpBinding, overwriting the UndertowHeaderFilterStrategy that DefaultUndertowHttpBinding installs by default — so the Undertow-specific strategy was constructed and immediately replaced before it could be consulted.
  • Trigger conditions: Occurs on endpoint-configured Undertow routes where no custom binding or explicit headerFilterStrategy is supplied. Rest DSL consumers are not affected, since UndertowComponent explicitly assigns UndertowRestHeaderFilterStrategy (which extends the Undertow strategy).
  • Attack vector: Network — an attacker sends an HTTP request to an Undertow HTTP consumer endpoint containing crafted websocket.* prefixed headers; these are mapped onto the Camel Exchange unfiltered and later interpreted by an Undertow WebSocket producer as dispatch directives.
  • Impact: Messages can be redirected to a WebSocket peer other than the one the route selected, and header names Undertow would otherwise reject are passed through to the Exchange rather than filtered.

Affected software

  • Apache Camel camel-undertow: 4.11.0 up to (but not including) 4.14.9
  • Apache Camel camel-undertow: 4.15.0 up to (but not including) 4.18.4
  • Apache Camel camel-undertow: 4.19.0 up to (but not including) 4.22.0

Severity

CVSS v3.1 Base Score: 9.8 (Critical)
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Mitigation and recommended actions

  • Immediate: Upgrade to a fixed release: 4.14.9 (4.14.x LTS stream), 4.18.4 (4.18.x stream), or 4.22.0.
  • If upgrade is not immediately possible: Explicitly bind an UndertowHeaderFilterStrategy in the registry and reference it on the endpoint (e.g., undertow:http://0.0.0.0:8080/foo?headerFilterStrategy=#myStrategy), and additionally strip dispatch headers at the trust boundary with removeHeaders("websocket.*").
  • Note: Even after upgrading, the websocket.* values remain part of Undertow’s externally visible API and are read directly by UndertowProducer via in.getHeader, which bypasses any HeaderFilterStrategy. Routes that pass untrusted messages from a non-Undertow consumer into an Undertow producer must independently strip these headers, as the fix only restores filtering at the Undertow transport boundary.

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge