Description

In rw_t4t_update_file of rw_t4t.cc, there is a possible out-of-bounds write due to an integer overflow. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.8",
  "pubDate": "2026-10-05T19:17:20.873Z",
  "pubdate": "2026-10-05T19:17:20.873Z",
  "executiveSummary": "A critical vulnerability exists in the rw_t4t_update_file function within the rw_t4t.cc component, stemming from an integer overflow condition. This flaw facilitates an out-of-bounds write operation, potentially allowing a local attacker to corrupt memory structures.\nThe vulnerability carries a significant risk of local escalation of privilege (EoP), granting an attacker elevated permissions on the target system. The security defect is particularly dangerous as it does not require any additional execution privileges or user interaction to facilitate exploitation, making it a highly accessible vector for malicious actors.\nThe impact includes potential system instability, arbitrary code execution, or unauthorized administrative access, depending on the attacker's ability to control the overflowed data and the subsequent memory layout. Systems utilizing this component are at high risk if the overflow condition can be triggered via external or local input paths.",
  "technicalDetails": "The root cause of the vulnerability resides in the arithmetic logic within the rw_t4t_update_file function in rw_t4t.cc. The function performs calculations involving file offsets or buffer sizes without adequate validation, leading to an integer overflow during the processing of input data. When the overflow occurs, the resulting integer value wraps around to a small or negative value, which is subsequently used as a boundary check or offset in memory management operations.\nSpecifically, the out-of-bounds write occurs when the system allocates or accesses a memory buffer based on the overflowed size. If the application logic assumes the integer value remains within a safe range, it may proceed to perform a memory write beyond the intended destination buffer. This operation results in memory corruption in adjacent memory segments, which can be leveraged to overwrite sensitive data, pointers, or control structures in the process memory space.\nExploitation involves crafting malicious input designed to trigger the arithmetic overflow. Since no authentication or specialized execution privileges are required, an attacker can supply a specially crafted file or command that forces the execution flow into the vulnerable code path. Once the integer overflow is triggered, the subsequent out-of-bounds write provides an avenue for redirecting execution flow, such as overwriting function pointers or returning addresses, which leads to arbitrary code execution with the privileges of the affected service.\nBecause the vulnerability exists in a fundamental file update mechanism, the persistence of the exploit is high. The attack flow is characterized by: (1) Submission of input that triggers the flawed arithmetic in rw_t4t_update_file; (2) Triggering the integer overflow to bypass boundary checks; (3) Executing the out-of-bounds write to corrupt heap or stack memory; (4) Gaining control over the process execution flow to escalate privileges locally. The lack of user interaction requirements significantly lowers the barrier for exploitation, making it a critical threat to local system integrity."
}