CVE-2023-4039
Description
A vulnerability was found in GCC. The GCC's stack protection feature, enabled with the flag -fstack-protector, aims to detect buffer overflows in C/C++ function local variables that might allow an attacker to overwrite saved registers on the stack. If an attacker can modify saved register values, it may be possible for them to subvert program flow control. The feature operates by placing a canary value between local variables and saved registers on the stack on function entry and triggers an error handler on function exit if the canary value has been unexpectedly modified.
When targeting AArch64, this feature did not protect the saved registers from overflows in C99-style dynamically-sized local variables and alloca() objects. Other local variables, including statically-sized local arrays, are not affected because of their different placement on the stack relative to saved registers.
Statement
According to the GCC security policy, both upstream and Red Hat Product Security do not consider this to be a vulnerability. Please refer to the following URLs for more information:
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
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).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 0 | 4.8 | 4.8 |
| Attack Vector | Network | Network | Network |
| Attack Complexity | High | High | High |
| Privileges Required | None | None | None |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | None | Low | Low |
| Integrity Impact | None | Low | Low |
| Availability Impact | None | None | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:N
NVD: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
cve.org: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Red Hat CVSS v3 Score Explanation
No security boundary is crossed. Red Hat Product Security does not consider this to be a vulnerability. Please refer to the Statement above.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
For an out-of-bounds read, the attacker may have access to sensitive information. If the sensitive information contains system details, such as the current buffer's position in memory, this knowledge can be used to craft further attacks, possibly with more severe consequences.
Integrity,Availability
Technical Impact: Modify Memory; DoS: Crash, Exit, or Restart
Out of bounds memory access will very likely result in the corruption of relevant memory, and perhaps instructions, possibly leading to a crash. Other attacks leading to lack of availability are possible, including putting the program into an infinite loop.
Integrity
Technical Impact: Modify Memory; Execute Unauthorized Code or Commands
If the memory accessible by the attacker can be effectively controlled, it may be possible to execute arbitrary code, as with a standard buffer overflow. If the attacker can overwrite a pointer's worth of memory (usually 32 or 64 bits), they can redirect a function pointer to their own malicious code. Even when the attacker can only modify a single byte arbitrary code execution can be possible. Sometimes this is because the same problem can be exploited repeatedly to the same effect. Other times it is because the attacker can overwrite security-critical application-specific data -- such as a flag indicating whether the user is an administrator.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
