A recently identified vulnerability under the code CVE-2022-35206 exposes a null pointer dereference in Binutils readelf 2.38.50. Specifically, the vulnerability exists in the function "read_and_display_attr_value" within the file "dwarf.c". This potential exploit has raised concerns among the software development community, as it may compromise system stability or even lead to unauthorized access.

In this post, we'll delve into the details of this vulnerability and provide insight on the root cause, code snippets, along with original references and more information on the exploit.

Details

A null pointer dereference occurs when a program inadvertently attempts to access the memory location represented by a null pointer. This can lead to unpredictable behavior, with consequences ranging from crashes to the potential for an attacker to execute arbitrary code.

In this particular case, the issue lies within the "read_and_display_attr_value" function in the "dwarf.c" file of Binutils readelf 2.38.50. To provide a better understanding of the problem, let's examine the relevant code snippet:

static int
read_and_display_attr_value (unsigned long type, unsigned long form,
                             unsigned char * data_ptr, unsigned char * end_ptr,
                             int indent, unsigned char * start, struct dwarf_section *section)
{
  ...
  if (start + length >= end_data)
    {
      error (_("Fetched an attribute value of %lu bytes which is beyond the scope of the next CU of size of %lu\n"),
             (unsigned long) length, (unsigned long) end_data - (unsigned long) start);
    }
  else
    {
      ...
      if (section->display)
        section->display (start, length, data); //<-- Null pointer dereference here
    }
  ...
}

The critical section in this snippet is the call to section->display. In certain situations, the "section" may be NULL, causing a null pointer dereference when the "display" function is invoked.

1. Binutils: The official homepage for the Binutils project.
2. Dwarf - Binutils readelf 2.38.50: The vulnerable "dwarf.c" file, hosted on the Binutils source repository.
3. CVE-2022-35206: The Mitre CVE entry for this vulnerability.

Exploit Details

While no publicly disclosed exploits currently target this vulnerability, its existence highlights the potential risk that could arise from an attacker successfully triggering the null pointer dereference. This might lead to a denial of service (DoS) attack or provide an attacker with an opportunity to execute arbitrary code.

To mitigate this vulnerability, developers are advised to update their Binutils package to the latest version. In the event that it's not feasible to immediately perform an update, developers should exercise caution when utilizing readelf 2.38.50 and monitor the software for any signs of abnormal behavior.

In conclusion, CVE-2022-35206 underscores the importance of proactively identifying and addressing security vulnerabilities in widely used tools like Binutils. By keeping ourselves informed and maintaining vigilance in applying updates, we can reduce the risk of potential exploits and keep our systems safe and secure.

Timeline

Published on: 08/22/2023 19:16:00 UTC
Last modified on: 08/31/2023 00:36:00 UTC