- Attack Vector: 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: 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: 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, or the attack may need to be launched multiple times against a single target before being successful); 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: Low
- The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
- User Interaction: Passive
- Successful exploitation of this vulnerability requires limited interaction by the targeted user with the vulnerable system and the attacker’s payload. These interactions would be considered involuntary and do not require that the user actively subvert protections built into the vulnerable system.
- Vulnerable system confidentiality: 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.
- Vulnerable system integrity: Low
- Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact to the Vulnerable System.
- Vulnerable system availability: None
- There is no impact to availability within the Vulnerable System.
- Subsequent system confidentiality: High
- There is a total loss of confidentiality, resulting in all resources within the Subsequent 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.
- Subsequent system integrity: None
- There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
- Subsequent system availability: None
- There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.
- Safety: Present
- Consequences of the vulnerability meet definition of IEC 61508 consequence categories of "marginal," "critical," or "catastrophic."
- Automatable: No
- Attackers cannot reliably automate all 4 steps of the kill chain for this vulnerability for some reason. These steps are reconnaissance, weaponization, delivery, and exploitation.
- Recovery: User
- The system requires manual intervention by the user to recover services, after an attack has been performed.
- Value Density: Diffuse
- The vulnerable system has limited resources. That is, the resources that the attacker will gain control over with a single exploitation event are relatively small. An example of Diffuse (think: limited) Value Density would be an attack on a single email client vulnerability.
- Vulnerability Response Effort: High
- The actions required to respond to a vulnerability are significant and/or difficult, and may possibly lead to an extended, scheduled service impact. This would need to be considered for scheduling purposes including honoring any embargo on deployment of the selected response. Alternatively, response to the vulnerability in the field is not possible remotely. The only resolution to the vulnerability involves physical replacement (e.g. units deployed would have to be recalled for a depot level repair or replacement). Examples include: a highly privileged driver update, microcode or UEFI BIOS updates, or software upgrades requiring careful analysis and understanding of any potential infrastructure impact before implementation. A UEFI BIOS update that impacts Trusted Platform Module (TPM) attestation without impacting disk encryption software such as Bit locker is a good recent example. Irreparable failures such as non-bootable flash subsystems, failed disks or solid-state drives (SSD), bad memory modules, network devices, or other non-recoverable under warranty hardware, should also be scored as having a High effort.
- Provider Urgency: Red
- Provider has assessed the impact of this vulnerability as having the highest urgency.
Definitions: FIRST CVSS v4.0 specification.