SQ18113
Detected Linux executable files that were compiled without the recommended dynamic symbol hijacking protections.
| priority | CI/CD status | severity | effort | RL level | RL assessment |
|---|---|---|---|---|---|
 | pass | medium | low | None | hardening: warning Reason: execution hijacking risks |
About the issue
On Linux, external symbols are resolved via the procedure linkage table (PLT) and the global offset table (GOT). Without any protection, both are writable at runtime and thus leave the executable vulnerable to pointer hijacking - an attack where the function address is overwritten with an address of a malicious function. Pointer hijacking can be mitigated by using full read-only relocations, which instruct the compiler to unify global offset tables into a single read-only table. This requires that all external function symbols are resolved at load-time instead of during execution, and may increase loading time for large programs.
How to resolve the issue
- In most cases, it's recommended to use full read-only relocations (in GCC: -Wl,-z,relro,-z,now).
- If the executable load-time is an issue, you should use partial read-only relocations.
Incidence statistics
ReversingLabs periodically collects and analyzes the contents of popular software package repositories for threat research purposes.
For every repository, the chart shows the percentage of projects that triggered the software assurance policy. In other words, it shows how many projects were found to have the specific issue described on this page.
The percentages are calculated from the total amount of packages analyzed:
- RubyGems: 174K
- Nuget: 189K
- PyPi: 403K
- NPM: 2.1M
Recommended reading
- Dynamic Linking (External resource - Linux Foundation)
- Hardening ELF binaries using Relocation Read-Only (RELRO) (External resource - Red Hat)
- Code Pointer Integrity (External resource - Medium)