CVE-2015-8777
It was found that the dynamic loader did not sanitize the LD_POINTER_GUARD environment variable. An attacker could use this flaw to bypass the pointer guarding protection on set-user-ID or set-group-ID programs to execute arbitrary code with the permissions of the user running the application.
Find out more about CVE-2015-8777 from the MITRE CVE dictionary dictionary and NIST NVD.
CVSS v2 metrics
| Base Score | 3.7 |
|---|---|
| Base Metrics | AV:L/AC:H/Au:N/C:P/I:P/A:P |
| Access Vector | Local |
| Access Complexity | High |
| Authentication | None |
| Confidentiality Impact | Partial |
| Integrity Impact | Partial |
| Availability Impact | Partial |
CVSS v3 metrics
| CVSS3 Base Score | 7 |
|---|---|
| CVSS3 Base Metrics | CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
| Attack Vector | Local |
| Attack Complexity | High |
| Privileges Required | Low |
| User Interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity Impact | High |
| Availability Impact | High |
Find out more about Red Hat support for the Common Vulnerability Scoring System (CVSS).
Red Hat Security Errata
| Platform | Errata | Release Date |
|---|---|---|
| Red Hat Enterprise Linux 7 (glibc) | RHSA-2017:1916 | 2017-08-01 |
Affected Packages State
| Platform | Package | State |
|---|---|---|
| Red Hat Enterprise Linux 6 | glibc | Will not fix |
| Red Hat Enterprise Linux 5 | glibc | Will not fix |
Mitigation
The glibc pointer guard is a post-exploitation mitigation mechanism. As such, it is only relevant if there are exploitable security vulnerabilities in the system. Therefore, applying available security updates to the system is a possible mitigation for this issue.
In typical deployments, environment variables can only be set by users with shell access. Restricting shell access to trusted users is another possible mitigation.