CVE-2023-40112: Exploring a Possible Out of Bounds Read in ippSetValueTag of ipp.c

In this long-read post, we will delve into the intricacies of a security vulnerability labeled as CVE-2023-40112. This vulnerability exists in the ippSetValueTag function found in the ipp.c file, and if exploited, could result in an out-of-bounds read due to a missing bounds check, potentially leading to local information disclosure. Furthermore, the exploitation of this vulnerability does not require user interaction or additional execution privileges.

Throughout this post, we will provide code snippets, links to original references, and exploit details to better grasp the implications of this vulnerability.

The Vulnerability: CVE-2023-40112

The CVE-2023-40112 vulnerability resides in the ippSetValueTag function of the ipp.c file. The function allows a possible out-of-bounds read due to the absence of a required bounds check. If exploited, this vulnerability could enable unauthorized users to access and disclose sensitive information, such as past print jobs or other print-related details, without any further execution privileges required.

The following code snippet showcases the vulnerable function in the ipp.c file

void ippSetValueTag(ipp_t *ipp, /* I - IPP message */
                    _ipp_value_t *value, /* I - Attribute value */
                    ipp_tag_t  ttag, /* I - New tag */
                    const void *data, /* I - New data */
                    size_t  count) /* I - Number of values */
{
  ...

  if (ttag == IPP_TAG_ENUM)
    attr->value.tag = (ipp_tag_t)(attr->value.tag & ~IPP_TAG_MASK);
  else
    attr->value.tag = ttag & ~IPP_TAG_MASK;

  if (attr->value.tag < IPP_TAG_MIMETYPE || (attr->value.tag >= IPP_TAG_ADMINDEFINE && attr->value.tag <= IPP_TAG_EXTENSION))
  {
    ...
    valptr = (char *)data;
    for (i = ; i < count; i ++)
    {
      memcpy(attr->values + i, valptr, (size_t)strlen((char *)valptr));
      valptr += strlen((char *)valptr); //<-- Possible out of bounds read
    }
  }
  ...
}

As seen in the above code snippet, the absence of the required bounds check allows the possibility of an out-of-bounds read when memcpy is called. Consequently, this creates a security loophole that can lead to local information disclosure.

Original References

For a deeper understanding of this vulnerability, the following links provide the original references:

1. NVD - CVE-2023-40112

2. MITRE - CVE-2023-40112

3. CWE-125: Out-of-bounds Read

Exploit Details

The exploitation of CVE-2023-40112 does not necessitate user interaction or additional execution privileges. In a real-world scenario, an attacker could craft malicious input that exploits the lack of bounds checking in the ippSetValueTag function. Consequently, the attacker may gain unauthorized access to sensitive information related to past print jobs or other print-related details.

Although no public exploit or proof-of-concept code currently exists, developers and administrators should remain vigilant, given the potential severity of successful exploitation.

Conclusion

To sum up, CVE-2023-40112 represents a potential security vulnerability that exists due to the absence of a required bounds check in the ippSetValueTag function within the ipp.c file. If exploited, unauthorized users could disclose sensitive print-related information without user interaction or additional execution privileges. By keeping a close eye on updates and patches, developers and administrators can mitigate the risk associated with this vulnerability and ensure the security of their systems.

Timeline

Published on: 02/15/2024 23:15:08 UTC
Last modified on: 02/16/2024 13:37:55 UTC