MountGitlab

Problem

Address Space Layout Randomization (ASLR) is a vulnerability mitigation option that forces software components to load on a different memory base address each time they are used. This mitigation is detected as enabled, but rendered ineffective due to the lack of code relocations necessary for layout randomization. This issue is reported for native 32-bit applications that contain code and opt in to use ASLR. Reasons for relocation absence include forcing software component load on a fixed address, removing relocations post-build, and using non-ASLR-compliant executable packing solutions.

Problem

Security Development Lifecycle (SDL) is a group of enhanced compile-time checks that report common coding mistakes as errors. These checks prevent the use of hard-to-secure string manipulation functions. They enforce static memory access checks, and allow only the use of range-verified string parsing functions. While these checks do not prevent every memory corruption issue by themselves, they do help reduce the likelihood.

Problem

Operating systems execute application code in multiple privilege access levels. Separation of privileges is designed to protect the stability and integrity of the operating system by shielding it from issues that the user run applications may cause. However, some users may need to interact with higher privilege parts of the operating system to accomplish specific tasks. For this purpose, operating systems provide facilities that users may leverage to temporarily elevate their running privileges. Users with higher privileges can run any application with the same privilege level as their own. Attackers often try to trick privileged users into running malicious code, enabling them to infect the operating system. While the presence of code that elevates user privileges does not necessarily imply malicious intent, all of its uses in a software package should be documented and approved. Only select applications should consider using functions that can elevate user privileges. One example of acceptable use for such functions is allowing the users to install software packages and updates.

Problem

Security Development Lifecycle (SDL) is a group of enhanced compile-time checks that report common coding mistakes as errors, preventing them from reaching production. These checks minimize the number of security issues by enforcing strict memory access checks. They also prevent the use of hard-to-secure string and memory manipulation functions. To prove the binary has been compiled with these checks enabled, the compiler emits a special debug object. Removing the debug table eliminates this proof. Therefore, this check only applies to binaries that still have their debug tables.

Problem

On Linux, external symbols are resolved via the procedure linkage table (PLT) and the global offset table (GOT). The global offset table is split into two tables - one for external data, and one for external functions. Without any protection, both are writable at runtime and thus leave the executable vulnerable to data overwrite attacks and pointer hijacking. Data overwrite attacks can be mitigated by using partial read-only relocations, while pointer hijacking can be mitigated with full read-only relocations. Both approaches have some drawbacks. Partial read-only relocations don't provide full protection, because the external function GOT remains writable. Full read-only relocations require that all external function symbols are resolved at load-time instead of during execution. This may increase loading time for large programs.