Google Android up to 4.4.1 Volume Management Daemon VolumeManager.cpp ID privileges management

Summaryinfo

A vulnerability was found in Google Android up to 4.4.1. It has been classified as problematic. Affected by this vulnerability is an unknown functionality of the file VolumeManager.cpp of the component Volume Management Daemon. Performing a manipulation of the argument ID results in privileges management. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Google Android up to 4.4.1 (Smartphone Operating System). This affects an unknown code block of the file VolumeManager.cpp of the component Volume Management Daemon. The manipulation of the argument id with an unknown input leads to a privileges management vulnerability. CWE is classifying the issue as CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. This is going to have an impact on confidentiality, and integrity. The advisory summarizes:

Vold (Volume Management Daemon) is a daemon running as root, which main goal is to handle removable media devices. ASEC are secured containers allowing applications to securely store data on the SD card, and have been introduced back in 2010. These containers have been created because the SD Card filesystem (VFAT) does not allow privileges separation.

The weakness was released 06/03/2014 by Fabien Perigaud with CERT-LEXSI as Local root vulnerability in Android 4.4.2 as not defined blog post (Website). It is possible to read the advisory at blog.cassidiancybersecurity.com. Attacking locally is a requirement. The requirement for exploitation is a authentication. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK. The advisory points out:

there is no check on the "id" variable, which is the name given by the user to its ASEC container. It is therefore possible to perform a basic path traversal, to create the ASEC file and its mount point in a different directory than expected, as for example one the "attacker" can write into. (...) This means that if the mount point already exists, no error is raised, and the container is correctly mounted in "mountPoint". Guess what? If "mountPoint" already exists AND is a symlink to an existing directory, the ASEC container will be mounted over this directory. And the user will have full access to it, allowing him to write new files inside.

Upgrading to version 4.4.2 eliminates this vulnerability. The vulnerability will be addressed with the following lines of code:

bool VolumeManager::isLegalAsecId(const char *id) const {
  size_t i;
  size_t len = strlen(id);

  if (len == 0) {
    return false;
  }
  if ((id[0] == '.') || (id[len - 1] == '.')) {
    return false;
  }

  for (i = 0; i < len; i++) {
    if (id[i] == '.') {
      // i=0 is guaranteed never to have a dot. See above.
      if (id[i-1] == '.') return false;
      continue;
    }
    if (id[i] == '_' || id[i] == '-') continue;
    if (id[i] >= 'a' && id[i] <= 'z') continue;
    if (id[i] >= 'A' && id[i] <= 'Z') continue;
    if (id[i] >= '0' && id[i] <= '9') continue;
    return false;
  }

  return true;
}

Google has now added a call to a new function "isLegalAsecId()" at the beginning of each function dealing with ASEC ids.

Further details are available at twitter.com. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Smartphone Operating System

Vendor

• Google

Name

• Android

Version

• 1.0
• 1.1
• 1.5
• 1.6
• 2.0
• 2.0.1
• 2.1
• 2.2
• 2.2.1
• 2.2.2
• 2.2.3
• 2.3
• 2.3.1
• 2.3.2
• 2.3.3
• 2.3.4
• 2.3.5
• 2.3.6
• 2.3.7
• 3.0
• 3.1
• 3.2
• 3.2.1
• 3.2.2
• 3.2.3
• 3.2.4
• 3.2.5
• 3.2.6
• 4.0
• 4.0.1
• 4.0.2
• 4.0.3
• 4.0.4
• 4.1
• 4.1.1
• 4.1.2
• 4.2
• 4.2.1
• 4.2.2
• 4.3
• 4.3.1
• 4.4
• 4.4.1

License

• free

Website

• Vendor: https://www.google.com/

CPE 2.3info

• 🔍
• 🔍
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CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

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