CVE Vulnerabilities

CVE-2015-6789

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Published: Dec 14, 2015 | Modified: Apr 12, 2025
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
9.3 HIGH
AV:N/AC:M/Au:N/C:C/I:C/A:C
RedHat/V2
6.8 IMPORTANT
AV:N/AC:M/Au:N/C:P/I:P/A:P
RedHat/V3
Ubuntu
MEDIUM

Race condition in the MutationObserver implementation in Blink, as used in Google Chrome before 47.0.2526.80, allows remote attackers to cause a denial of service (use-after-free) or possibly have unspecified other impact by leveraging unanticipated object deletion.

Weakness

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

Affected Software

Name Vendor Start Version End Version
Chrome Google * 47.0.2526.73 (including)
Red Hat Enterprise Linux 6 Supplementary RedHat chromium-browser-0:47.0.2526.80-1.el6 *
Chromium-browser Ubuntu devel *
Chromium-browser Ubuntu precise *
Chromium-browser Ubuntu trusty *
Chromium-browser Ubuntu upstream *
Chromium-browser Ubuntu vivid *
Chromium-browser Ubuntu wily *
Oxide-qt Ubuntu devel *
Oxide-qt Ubuntu trusty *
Oxide-qt Ubuntu upstream *
Oxide-qt Ubuntu vivid *
Oxide-qt Ubuntu vivid/stable-phone-overlay *
Oxide-qt Ubuntu wily *

Extended Description

A race condition occurs within concurrent environments, and it is effectively a property of a code sequence. Depending on the context, a code sequence may be in the form of a function call, a small number of instructions, a series of program invocations, etc. A race condition violates these properties, which are closely related:

A race condition exists when an “interfering code sequence” can still access the shared resource, violating exclusivity. The interfering code sequence could be “trusted” or “untrusted.” A trusted interfering code sequence occurs within the product; it cannot be modified by the attacker, and it can only be invoked indirectly. An untrusted interfering code sequence can be authored directly by the attacker, and typically it is external to the vulnerable product.

Potential Mitigations

  • Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring.
  • Additionally, this will minimize the amount of synchronization necessary and may even help to reduce the likelihood of a denial of service where an attacker may be able to repeatedly trigger a critical section (CWE-400).

References