CVE-2026-19741
19h56 +00:00
CVE の説明
OpenThread joiner autostart uses a publicly documented default Joining Device Credential (PSKd)
Zephyr's OpenThread integration defined CONFIG_OPENTHREAD_JOINER_PSKD with default "J01NME" in modules/openthread/Kconfig.thread (previously subsys/net/l2/openthread/Kconfig, then subsys/net/l2/openthread/Kconfig.thread). J01NME is the example Joining Device Credential used throughout the public OpenThread and Thread commissioning documentation, including Zephyr's own samples/net/sockets/echo_client/README.rst, so it is not a secret. A firmware image built with CONFIG_OPENTHREAD_JOINER_AUTOSTART=y that never overrode the PSKd therefore shipped with a publicly known joining credential compiled in, with no build-time or run-time warning. The PSKd is the only value that authenticates Thread commissioning: joiner and commissioner run a DTLS-PSK handshake keyed on it, after which the commissioner supplies the full operational dataset. In ot_configure_instance() (modules/openthread/openthread.c), a device with no stored dataset calls otJoinerStart() with the configured PSKd, and ot_joiner_start_handler() calls otThreadSetEnabled() on success. An unauthenticated attacker within 802.15.4 radio range of an uncommissioned device (factory-fresh, after a factory reset, or after a settings erase) can run any stock Thread commissioner registered with J01NME, complete the handshake, and hand the device an attacker-controlled operational dataset. The device then joins and enables Thread on the attacker's mesh. The attacker becomes its router, seeing, dropping, injecting and spoofing all of the device's IPv6 traffic and impersonating the peers the application expects, while the device is cut off from the network it was meant to join and stays mis-provisioned until it is reset. Only application-layer security with independently provisioned credentials survives. Exposure is limited to builds that enable joiner autostart and leave the PSKd unset; the option is not enabled by default and no in-tree sample uses the vulnerable combination. The fix removes the default from CONFIG_OPENTHREAD_JOINER_PSKD and adds a BUILD_ASSERT() in modules/openthread/openthread.c, active only under CONFIG_OPENTHREAD_JOINER_AUTOSTART, that fails the build unless a 6-to-32-character PSKd is configured. Products should provision a per-device PSKd from factory data and call otJoinerStart() from the application rather than relying on a credential compiled identically into every unit.CVE の情報
関連する弱点
| 弱点名 | 出典 | |
|---|---|---|
| Use of Default Credentials The product uses default credentials (such as passwords or cryptographic keys) for potentially critical functionality. |
メトリクス
| メトリクス | スコア | 深刻度 | CVSS ベクター | 出典 |
|---|---|---|---|---|
| V3.1 | 7.5 | HIGH |
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
詳細情報
Base: Exploitabilty MetricsThe Exploitability metrics reflect the characteristics of the thing that is vulnerable, which we refer to formally as the vulnerable component. Attack Vector This metric reflects the context by which vulnerability exploitation is possible. Adjacent The vulnerable component is bound to the network stack, but the attack is limited at the protocol level to a logically adjacent topology. This can mean an attack must be launched from the same shared physical (e.g., Bluetooth or IEEE 802.11) or logical (e.g., local IP subnet) network, or from within a secure or otherwise limited administrative domain (e.g., MPLS, secure VPN to an administrative network zone). Attack Complexity This metric describes the conditions beyond the attacker’s control that must exist in order to exploit the vulnerability. High successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. Privileges Required This metric describes the level of privileges an attacker must possess before successfully exploiting the vulnerability. None The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack. User Interaction This metric captures the requirement for a human user, other than the attacker, to participate in the successful compromise of the vulnerable component. None The vulnerable system can be exploited without interaction from any user. Base: Scope MetricsThe Scope metric captures whether a vulnerability in one vulnerable component impacts resources in components beyond its security scope. Scope Formally, a security authority is a mechanism (e.g., an application, an operating system, firmware, a sandbox environment) that defines and enforces access control in terms of how certain subjects/actors (e.g., human users, processes) can access certain restricted objects/resources (e.g., files, CPU, memory) in a controlled manner. All the subjects and objects under the jurisdiction of a single security authority are considered to be under one security scope. If a vulnerability in a vulnerable component can affect a component which is in a different security scope than the vulnerable component, a Scope change occurs. Intuitively, whenever the impact of a vulnerability breaches a security/trust boundary and impacts components outside the security scope in which vulnerable component resides, a Scope change occurs. Unchanged An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority. Base: Impact MetricsThe Impact metrics capture the effects of a successfully exploited vulnerability on the component that suffers the worst outcome that is most directly and predictably associated with the attack. Analysts should constrain impacts to a reasonable, final outcome which they are confident an attacker is able to achieve. Confidentiality Impact This metric measures the impact to the confidentiality of the information resources managed by a software component due to a successfully exploited vulnerability. High There is a total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server. Integrity Impact This metric measures the impact to integrity of a successfully exploited vulnerability. Integrity refers to the trustworthiness and veracity of information. High There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component. Availability Impact This metric measures the impact to the availability of the impacted component resulting from a successfully exploited vulnerability. High There is a total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable). Temporal MetricsThe Temporal metrics measure the current state of exploit techniques or code availability, the existence of any patches or workarounds, or the confidence in the description of a vulnerability. Environmental MetricsThese metrics enable the analyst to customize the CVSS score depending on the importance of the affected IT asset to a user’s organization, measured in terms of Confidentiality, Integrity, and Availability. |
