CVE 描述

Improper authentication lets Google sign-in and confirmation links sign users in to accounts registered with their email address by someone else

Improper Authentication vulnerability in Google sign-in and email confirmation in nerves-hub nerves_hub_web allows an attacker who registers another person's email address to share that person's account once they sign in. NervesHub.Accounts.update_or_create_user_from_ueberauth/1 signs a Google user in to any account carrying the same email that is not yet linked to a Google account, links it and marks the email confirmed, without the account's owner ever having proved they own the address. NervesHubWeb.SessionController.confirm/2 likewise signs in whoever follows a confirmation link. An attacker registers the address from the sign-up form, changes their own account's email to it, or registers it as an organization admin from an invite link, and keeps the password; when the address's owner signs in with Google or follows the confirmation link, they land in that account. The Google path also creates accounts with registrations closed and never checks Google's email_verified claim, and the API's password sign-in in NervesHubWeb.API.UserController issues tokens to accounts whose email was never confirmed. The attacker gains only what the victim is granted afterwards, and nothing on accounts whose owners never use either path. This issue affects nerves_hub: from 2.3.0 before 2.5.3.

CVE 解決方案

Upgrading does not undo links already made. Review the users rows that carry both a password_hash and a google_id; most are one person signing in both ways, but an account registered for someone else's address was usually created well before its first Google sign-in, so compare inserted_at with google_last_synced_at. For one its owner did not set up, set its google_id to NULL, delete its user_tokens rows to end its sessions and revoke its API tokens, and have the address's owner reset the password. An account taken through a confirmation link looks the same as one its owner set up; its owner can end anyone else's access by resetting the password, which ends every session and revokes every API token. Before upgrading, check how your instance lets people sign up: SIGN_UP_METHODS replaces OPEN_FOR_REGISTRATIONS, and instances that relied on Google sign-in to create accounts while registrations were off need SIGN_UP_METHODS=google.

CVE 資訊

相關弱點

CWE-ID	弱點名稱	來源
CWE-287	Improper Authentication When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
CWE-345	Insufficient Verification of Data Authenticity The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.

指標

指標	評分	嚴重程度	CVSS 向量	來源
V4.0	7.4	HIGH	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N 更多資訊 Base: Exploitabilty Metrics The Exploitability metrics reflect the characteristics of the “thing that is vulnerable”, which we refer to formally as the vulnerable system. Attack Vector This metric reflects the context by which vulnerability exploitation is possible. Network The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers). Attack Complexity This metric captures measurable actions that must be taken by the attacker to actively evade or circumvent existing built-in security-enhancing conditions in order to obtain a working exploit. Low The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system. Attack Requirements This metric captures the prerequisite deployment and execution conditions or variables of the vulnerable system that enable the attack. Present The successful attack depends on the presence of specific deployment and execution conditions of the vulnerable system that enable the attack. These include: A race condition must be won to successfully exploit the vulnerability. The successfulness of the attack is conditioned on execution conditions that are not under full control of the attacker. The attack may need to be launched multiple times against a single target before being successful. Network injection. The attacker must inject themselves into the logical network path between the target and the resource requested by the victim (e.g. vulnerabilities requiring an on-path attacker). Privileges Required This metric describes the level of privileges an attacker must possess prior to successfully exploiting the vulnerability. None The attacker is unauthenticated 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 system. Active Successful exploitation of this vulnerability requires a targeted user to perform specific, conscious interactions with the vulnerable system and the attacker’s payload, or the user’s interactions would actively subvert protection mechanisms which would lead to exploitation of the vulnerability. Examples include: importing a file into a vulnerable system in a specific manner placing files into a specific directory prior to executing code submitting a specific string into a web application (e.g. reflected or self XSS) dismiss or accept prompts or security warnings prior to taking an action (e.g. opening/editing a file, connecting a device). Base: Impact Metrics The Impact metrics capture the effects of a successfully exploited vulnerability. 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 managed by the system due to a successfully exploited vulnerability. High There is a total loss of confidentiality, resulting in all information within the Vulnerable System 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. 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 Vulnerable System. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the Vulnerable System. Availability Impact This metric measures the impact to the availability of the impacted system resulting from a successfully exploited vulnerability. None There is no impact to availability within the Vulnerable System. Sub Confidentiality Impact Negligible There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System. Sub Integrity Impact None There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System. Sub Availability Impact None There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System. Threat Metrics The Threat metrics measure the current state of exploit techniques or code availability for a vulnerability. Environmental Metrics These metrics enable the consumer analyst to customize the resulting score depending on the importance of the affected IT asset to a user’s organization, measured in terms of complementary/alternative security controls in place, Confidentiality, Integrity, and Availability. The metrics are the modified equivalent of Base metrics and are assigned values based on the system placement within organizational infrastructure. Supplemental Metrics Supplemental metric group provides new metrics that describe and measure additional extrinsic attributes of a vulnerability. While the assessment of Supplemental metrics is provisioned by the provider, the usage and response plan of each metric within the Supplemental metric group is determined by the consumer.