CVE-2026-108946Apache ActiveMQ improper input validation
CVE-2026-108946 is a improper input validation in Apache ActiveMQ, rated medium (6.5 on CVSS 3.1).
Why this priority: Medium severity, with no exploitation signal.
Published · Updated · NVD status: Awaiting Analysis
What it is
The software trusts input it should check, so crafted values reach code that assumes they are well formed.
How it is reached
An attacker can exploit it over the network, with an ordinary user account, and nobody has to click anything.
What an attacker gains
A successful attack can change data or behaviour. In practice, this kind of flaw lets an attacker drive the component into behaviour its authors did not intend.
Is it being exploited?
There is no public report of exploitation yet. EPSS estimates a 0.23% chance of exploitation activity in the next 30 days, higher than 14% of scored CVEs.
What to do
- Upgrade Apache ActiveMQ to a fixed version for your release line (6.3.3, 5.19.12). Other affected products have their own fixed versions on this page.
- Until it is patched, review who holds accounts that can reach it.
Description from NVD
Improper input validation vulnerability in Apache ActiveMQ, Apache ActiveMQ KahaDB.
The ActiveMQ broker resolves connection, session and consumer state from ids that are user provided and in some scenarios does not validate that they ids are bound to that user. This allows an authenticated client to spoof another user's ids. This allows:
* an authenticated client consumes from another connection's temporary queue/topic by putting the victim's connection id in its own ConsumerId, bypassing the broker-side ownership check. * a duplicate ConsumerId registration is only logged, after which the attacker's RemoveInfo or disconnect tears down the victim's live subscription * a forged MessageAck for the victim's ConsumerId permanently deletes an in-flight, unacknowledged message.
This issue affects Apache ActiveMQ: from 6.0.0 before 6.3.3, before 5.19.12; Apache ActiveMQ KahaDB: from 6.0.0 before 6.3.3, before 5.19.12.
Users are recommended to upgrade to version 6.4.0, 6.3.3, or 5.19.12, which fixes the issue.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Interfaces that accept external input. The flaw sits at the input boundary of the affected component.
Trust boundaries in play
- Authenticated network access. An account is needed, so exposure follows who can sign in: customers, partners or staff.
- At the input boundary of the affected component. An attacker who crosses it can drive the component into behaviour its authors did not intend.
Questions to answer about your own systems
- Where does Apache ActiveMQ run in your systems, and at which version?
- Which of those instances can be reached from the internet or partner networks?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.