CVE-2017-7308
Description
It was found that the packet_set_ring() function of the Linux kernel's networking implementation did not properly validate certain block-size data. A local attacker with CAP_NET_RAW capability could use this flaw to trigger a buffer overflow resulting in a system crash or a privilege escalation.
Statement
This issue does not affect Red Hat Enterprise Linux 5.
In a default or common use of Red Hat Enterprise Linux 6 and 7 this issue does not allow an unprivileged local user elevate their privileges on the system. In order to exploit this issue the attacker needs CAP_NET_RAW capability, which needs to be granted by the administrator to the attacker's account. Since Red Hat Enterprise Linux 6 does not have namespaces support and Red Hat Enterprise Linux 7 does not have unprivileged user namespaces enabled by default, local unprivileged users also cannot abuse namespaces feature to grant this capability to themselves and elevate their privileges.
So, this issue does not affect Red Hat Enterprise Linux 6, 7 and Red Hat Enterprise MRG 2 in the default configuration. Future updates for the respective releases will address this issue to secure non-default configurations.
In the non-default configuration mentioned above only Red Hat Enterprise Linux 7 is vulnerable to a privilege escalation. Red Hat Enterprise Linux 6 is vulnerable only to a denial of service (DoS) due to a system crash, hence the impact on Red Hat Enterprise Linux 6 is rated as being Moderate.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7 | 7.8 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | High | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | High | High | N/A |
| Integrity Impact | High | High | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability
Technical Impact: Modify Memory; Execute Unauthorized Code or Commands
Buffer overflows often can be used to execute arbitrary code, which is usually outside the scope of the product's implicit security policy. This can often be used to subvert any other security service.
Availability
Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU)
Buffer overflows generally lead to crashes. Other attacks leading to lack of availability are possible, including putting the product into an infinite loop.
Frequently Asked Questions
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