---
id: "CVE-2026-84181"
kind: "vulnerability"
aliases: ["CVE-2026-84181"]
title: "Apache Camel Shiro: credentials skipped when thread reuses a bound subject"
severity: "medium"
cvss: 5.9
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["apache-camel", "integration", "java", "package", "shiro"]
not_affected_if: ["default-config", "no-camel-shiro"]
published_at: "2026-10-19T11:17:22+00:00"
first_seen_at: "2026-10-23T21:57:18+00:00"
updated_at: "2026-10-25T04:08:51+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84181", "first_seen_at": "2026-10-23T21:57:18+00:00"}]
---

# Apache Camel Shiro: credentials skipped when thread reuses a bound subject

The Shiro security processor in Apache Camel skips password verification when the thread's bound subject has the same principal as the incoming exchange. Because threads are pooled, an attacker who sends a request naming an active principal can get through without valid credentials.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the Camel version in the project's dependency files (for example `camel-shiro` in pom.xml or build.gradle) and compare it to the affected ranges: 4.0.0 to before 4.18.5, or 4.19.0 to before 4.22.1.
- Look for uses of the Shiro security processor and check whether `alwaysReauthenticate` is set to `false`.

## Fix

- Upgrade Apache Camel to `4.23.0`, or to `4.18.5` on the 4.18.x LTS stream, or `4.22.1` on the 4.22.x LTS stream.
- If upgrading is not possible right away, set `alwaysReauthenticate=false` only if the deployment depends on the old behaviour, and make sure the Shiro subject is cleared from the thread at the end of every exchange.

## Timeline

- 2026-10-23T21:57:18+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-84181

## From the sources

Improper Authentication vulnerability in Apache Camel Shiro component.



This issue affects Apache Camel: from 4.0.0 before 4.18.5, from 4.19.0 before 4.22.1.

The Shiro security processor skipped credential verification when the subject already bound to the current thread carried the same principal as the incoming exchange. Because the thread that carries a Camel exchange is drawn from a pool and reused across exchanges, a subject left bound by an earlier authenticated exchange could satisfy the check for a later one that presented no valid credentials of its own. The password on the incoming exchange was, in that case, never verified. The condition depends on thread reuse and on the principal matching, which is why it is not reached on every request, but it requires nothing of the attacker beyond sending a request naming a principal that is in active use.

Upgrade to Apache Camel 4.23.0, which fixes the issue. Users on the 4.18.x LTS releases stream should upgrade to 4.18.5. Users on the 4.22.x LTS releases stream should upgrade to 4.22.1. The processor now verifies the presented credentials on every exchange rather than accepting a subject already bound to the thread. Setting alwaysReauthenticate=false restores the previous behaviour for deployments that depend on it. For deployments that cannot upgrade immediately, ensure the Shiro subject is cleared from the thread at the end of every exchange so that no subject can be inherited by a later one.

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