CVE の説明

SQL injection via unescaped dollar-quote in Postgrex.Notifications reconnect replay causes notification denial of service

SQL Injection vulnerability in elixir-ecto postgrex allows an attacker who can influence a LISTEN channel name to inject SQL into the reconnect replay query, causing a denial of service of the notification connection. Postgrex.Notifications sanitizes channel names with quote_channel/1, which doubles double quotes so the name is safe inside a double-quoted identifier. This protects the single-statement LISTEN and UNLISTEN paths. On every (re)connect, however, handle_connect/1 replays all registered channels at once by concatenating their LISTEN statements and wrapping them in a dollar-quoted anonymous code block (DO $$BEGIN ... END$$). quote_channel/1 does not escape the $$ dollar-quote delimiter that opens and closes this block. The listen/3 guards only reject null bytes and names longer than 63 bytes, so a channel name containing $$ passes validation unchanged. Once such a name is embedded, its $$ prematurely terminates the outer dollar-quoted string and PostgreSQL parses the remainder as additional top-level statements. Because handle_connect/1 runs on every (re)connect, the malformed replay query is rejected each time and the notification connection never re-establishes its subscriptions, silently dropping notifications for every channel sharing that connection. An application is affected when it passes untrusted input (for example a tenant or user identifier) as a channel name to Postgrex.Notifications.listen/3. The double-quote doubling prevents forming a fully valid injected statement, so arbitrary SQL execution is not possible, but the corrupted query reliably breaks the shared notification connection for all tenants, resulting in denial of service. This issue affects postgrex: from 0.16.0 before 0.22.3.

CVE の情報

関連する弱点

CWE-ID	弱点名	出典
CWE-89	Improper Neutralization of Special Elements used in an SQL Command The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.

メトリクス

メトリクス	スコア	深刻度	CVSS ベクター	出典
V4.0	2.1	LOW	CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N 詳細情報 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. Local The vulnerable system is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or through terminal emulation (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., using social engineering techniques to trick a legitimate user into opening a malicious document). 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. None The vulnerable system can be exploited without interaction from any human user, other than the attacker. Examples include: a remote attacker is able to send packets to a target system a locally authenticated attacker executes code to elevate privileges 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. None There is no loss of confidentiality within the Vulnerable System. Integrity Impact This metric measures the impact to integrity of a successfully exploited vulnerability. None There is no loss of integrity within the Vulnerable System. Availability Impact This metric measures the impact to the availability of the impacted system resulting from a successfully exploited vulnerability. Low Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Vulnerable System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to 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.