CVE-2025-56365 Overview
CVE-2025-56365 is a reachable assertion vulnerability in the Matter SDK (connectedhomeip) before version 1.4.0. The flaw resides in the interaction model command processing logic. When an attacker sends an InvokeCommandRequest targeting a nonexistent endpoint and cluster such as 0x34, the code treats the endpoint as valid. Missing validation checks in CodegenDataModelProvider::Invoke cause a VerifyOrDie failure inside ProcessCommandDataIB, which terminates the process with SIGABRT. The result is a remote denial of service against Matter-based smart home and IoT devices. The Connectivity Standards Alliance acknowledged the issue and merged a fix in pull request #37207.
Critical Impact
Unauthenticated network-based attackers can crash any Matter device running an affected version of connectedhomeip, disrupting smart home and IoT deployments.
Affected Products
- CSA-IoT Matter SDK (connectedhomeip) versions before 1.4.0
- Smart home devices and controllers built on the Matter protocol stack
- IoT gateways and hubs bundling the affected connectedhomeip library
Discovery Timeline
- 2026-07-14 - CVE-2025-56365 published to NVD
- 2026-07-17 - Last updated in NVD database
Technical Details for CVE-2025-56365
Vulnerability Analysis
The vulnerability is a reachable assertion classified under [CWE-617]. Matter's interaction model handles command invocation through InvokeCommandRequest messages, which specify a target endpoint and cluster. The processing pipeline in connectedhomeip is expected to validate that both the endpoint and cluster exist before dispatching the command. In affected versions the endpoint validation is incomplete, so requests directed at nonexistent endpoints proceed further into the dispatch logic than they should.
Once control reaches ProcessCommandDataIB, an internal invariant assumes the endpoint identifier is valid. The invariant is enforced with VerifyOrDie, which aborts the process when the check fails. An attacker only needs network reachability to a Matter node to trigger the abort, and no authentication or user interaction is required.
Root Cause
The root cause is missing endpoint and cluster existence checks in CodegenDataModelProvider::Invoke. The function forwards the request into command dispatch without confirming the endpoint is registered in the data model. Downstream code then relies on VerifyOrDie as a defensive check, but VerifyOrDie is a hard abort rather than a graceful error path. The mismatch between optimistic upstream handling and strict downstream assertion converts a malformed request into a process crash.
Attack Vector
Exploitation requires sending a single crafted InvokeCommandRequest over the network to a Matter device. The attacker specifies an endpoint identifier and a cluster identifier such as 0x34 that are not present in the device's data model. Processing the request triggers the assertion and terminates the Matter process with SIGABRT. Repeated requests can keep the device offline indefinitely, disrupting device pairing, command delivery, and automation flows across a smart home deployment.
No public proof-of-concept exploit is listed for this CVE, and the vulnerability is not present in the CISA Known Exploited Vulnerabilities catalog. Technical details are available in the upstream project's GitHub Issue #37184 and the fix in GitHub Pull Request #37207.
Detection Methods for CVE-2025-56365
Indicators of Compromise
- Unexpected SIGABRT termination of Matter processes with stack frames referencing ProcessCommandDataIB or VerifyOrDie.
- Repeated device reboots or Matter service restarts on IoT hubs shortly after receiving inbound Matter traffic.
- Inbound InvokeCommandRequest messages targeting endpoint or cluster identifiers that are not defined on the receiving device.
Detection Strategies
- Inspect Matter protocol traffic for InvokeCommandRequest frames referencing cluster IDs such as 0x34 that do not exist on the target device.
- Monitor host and container logs for abort signals and core dumps produced by connectedhomeip binaries.
- Correlate device availability metrics with network events to identify crash-loop patterns triggered by external traffic.
Monitoring Recommendations
- Enable crash reporting and core dump collection on Matter controllers, hubs, and bridges to capture assertion failures.
- Forward Matter service logs to a centralized log platform and alert on repeated process restarts.
- Baseline normal Matter command traffic per device and alert on requests targeting undefined endpoints or clusters.
How to Mitigate CVE-2025-56365
Immediate Actions Required
- Upgrade connectedhomeip to version 1.4.0 or later, which includes the fix from pull request #37207.
- Contact device vendors for firmware updates that incorporate the patched Matter SDK.
- Restrict Matter network access to trusted local network segments until affected devices are updated.
Patch Information
The Connectivity Standards Alliance addressed the issue in GitHub Pull Request #37207 against the project-chip/connectedhomeip repository. The fix adds the missing endpoint and cluster validation in CodegenDataModelProvider::Invoke so that requests targeting nonexistent endpoints are rejected before reaching the VerifyOrDie check. Downstream vendors must rebuild and redistribute firmware that links against the patched SDK.
Workarounds
- Segment Matter devices onto a dedicated VLAN or Thread network with strict ingress filtering.
- Block untrusted hosts from initiating Matter fabric communication with production devices.
- Enable automatic restart with rate limiting on Matter services to reduce sustained downtime from crash loops.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
