CVE-2011-0470

CVE: CVE-2011-0470
CWE:
- 435
bugs:
- 58053
repo: 
vccs:
- note: |
    This commit was made by user 'Oshima'. This person is adding
    the notification panel for chromeos here, and they don't properly handle
    closing all the balloons. In his commit message, he states that he had to
    remove some animation code because a part of the browser no longer understood
    how to render its view, and that he 'needs to think a bit more to find out how
    to deal with this'. It seems that the animation code somehow played a role in the collection
    process of the balloons. He also states that it uses an existing balloon collection,
    and that another one may be needed for chromeos. It is clear now that balloon
    collection was not handled properly and required a fix later on.
  commit: 2e5cc5f3deae4aa459b8d5f9188c7cf766b7c08f
fixes:
- note: "Commit was made to multiple files all pertaining to the\nnotifications subsystem.
    JohnnyG added a collection system that\ngathered all open notification balloons
    (which are pop-up \nnotifications that take the form of dialogues on the web page)
    \nand closed them thus stopping the application from crashing\n"
  commit: ad085262f5203816bd8949720e3df9aba9147b4e
bounty:
  date: 
  amount: 
  references: []
lessons:
  yagni:
    note: 
    applies: 
  question: |
    Are there any common lessons we have learned from class that apply to this
    vulnerability? In other words, could this vulnerability serve as an example
    of one of those lessons?

    Leave "applies" blank or put false if you did not see that lesson (you do
    not need to put a reason). Put "true" if you feel the lesson applies and put
    a quick explanation of how it applies.

    Don't feel the need to claim that ALL of these apply, but it's pretty likely
    that one or two of them apply.

    If you think of another lesson we covered in class that applies here, feel
    free to give it a small name and add one in the same format as these.
  serial_killer:
    note: 
    applies: 
  complex_inputs:
    note: 
    applies: 
  distrust_input:
    note: 
    applies: 
  least_privilege:
    note: 
    applies: 
  native_wrappers:
    note: 
    applies: 
  defense_in_depth:
    note: |
      Defense in depth applies here because there were multiple layers of the
      system that needed to change in order to fix this issue. Commits were made in
      about 10 different files, all to collect balloons and properly close them. This
      shows the complexity of the system and the measures that were taken to ensure that
      there are numerous layers that work together in a single moving piece.
    applies: true
  secure_by_default:
    note: 
    applies: 
  environment_variables:
    note: 
    applies: 
  security_by_obscurity:
    note: 
    applies: 
  frameworks_are_optional:
    note: 
    applies: 
reviews:
- 5581002
- 5585003
- 5743004
- 5798001
- 5533004
- 5319011
- 5754003
upvotes: 
mistakes:
  answer: |
    This vulnerability is a result of chrome not properly handling extensions
    notification, allowing remote attackers to cause a system crash. The root
    of this problem could be found in the notifications subsystem. Generally,
    when you have something open in your code, when you finish using it, it is
    important to properly collect and close anything that is left. The issue
    that occured here is that the notification 'balloons' were not properly
    collected before attempting to close them. This led to a race condition
    that happened on shut down. The browser would stop all rendering and force
    windows to close. The code in the notifications subsystem would then detect
    the renderer being shut down as well, and attempt to close the window a
    second time. The fix was introduced by properly collecting all notification
    balloons on shut down, and closing all of those first. This way, there is
    nothing left to try and close the window a second time after the window
    already shuts down. This looks like a proper fix, and addresses the issue
    at multiple points in the system.
  question: |
    In your opinion, after all of this research, what mistakes were made that
    led to this vulnerability? Coding mistakes? Design mistakes?
    Maintainability? Requirements? Miscommunications?

    Look at the CWE entry for this vulnerability and examine the mitigations
    they have written there. Are they doing those? Does the fix look proper?

    Use those questions to inspire your answer. Don't feel obligated to answer
    every one. Write a thoughtful entry here that those ing the software
    engineering industry would find interesting.
announced: '2011-01-14 12:00:02.607000000 -05:00'
subsystem:
  name: Notifications
  answer: The notification subsystem
  question: |
    What subsystems was the mistake in?

    Look at the path of the source code files code that were fixed to get
    directory names. Look at comments in the code. Look at the bug reports how
    the bug report was tagged. Examples: "clipboard", "gpu", "ssl", "speech", "renderer"
discovered:
  date: '2010-10-05'
  answer: |
    User 'eroman' encountered a crash with chrome and opened up a bug report with his
    crash log. Other users struggled to recreate these issues at first, before figuring out that
    user 'eroman' had a new version of chrome installed, and there had likely been a regression in
    the notification subsystem.
  google: true
  contest: false
  question: |
    How was this vulnerability discovered?

    Go to the bug report and read the conversation to find out how this was
    originally found. Answer in longform below in "answer", fill in the date in
    YYYY-MM-DD, and then determine if the vulnerability was found by a Google
    employee (you can tell from their email address). If it's clear that the
    vulenrability was discovered by a contest, fill in the name there.

    The "automated" flag can be true, false, or nil.
    The "google" flag can be true, false, or nil.

    If there is no evidence as to how this vulnerability was found, then you may
    leave the entries blank except for "answer". Write down where you looked in "answer".
  automated: false
description: |
  This issue was reported on Oct. 5 2010 by chromium user 'Eroman', and fixed by
  user 'johnnyg' on Dec. 1 2010

  from the chromium Notifications subsystem

  Google chrome did not properly handle an extensions notifications, thus allowing
  remote attackers to cause the application to crash (denial of service) through the
  use of unspecified vectors.
unit_tested:
  fix: true
  code: true
  answer: |
    a single unit test was added to ensure this fix worked
      virtual void RemoveAll() {} <- this was the subsequent change to
      the balloon_controller_unittest.mm file
  question: |
    Were automated unit tests involved in this vulnerability?
    Was the original code unit tested, or not unit tested? Did the fix involve
    improving the automated tests?

    For the "code" answer below, look not only at the fix but the surrounding
    code near the fix and determine if and was there were unit tests involved
    for this module.

    For the "fix" answer below, check if the fix for the vulnerability involves
    adding or improving an automated test to ensure this doesn't happen again.
major_events:
  answer: 
  events:
  - date: 
    name: 
  - date: 
    name: 
  question: |
    Please record any major events you found in the history of this
    vulnerability. Was the code rewritten at some point? Was a nearby subsystem
    changed? Did the team change?

    The event doesn't need to be directly related to this vulnerability, rather,
    we want to capture what the development team was dealing with at the time.
curation_level: 1
CWE_instructions: |
  Please go to cwe.mitre.org and find the most specific, appropriate CWE entry
  that describes your vulnerability. (Tip: this may not be a good one to start
  with - spend time understanding this vulnerability before making your choice!)
bounty_instructions: |
  If you came across any indications that a bounty was paid out for this
  vulnerability, fill it out here. Or correct it if the information already here
  was wrong. Otherwise, leave it blank.
interesting_commits:
  answer: |
    After the VCC, the bug report was opened up. This led to people asking questions,
    uncovering the versions this bug occurs in. JohnnyG reports that he is looking into
    the situation. Numerous changes occur within the notification subsystem regarding
    the tracking and closing of balloon windows. It is eventually discovered that a race
    condition is causing the window to try and close out twice, and throws an error after
    trying to close a window that is already closed. JohnnyG creates the patch by rounding
    up all stray balloons in the chromeo notifications and closing them individually.
  commits:
  - note: 
    commit: 
  - note: 
    commit: 
  question: |
    Are there any interesting commits between your VCC(s) and fix(es)?

    Write a brief (under 100 words) description of why you think this commit was
    interesting in light of the lessons learned from this vulnerability. Any
    emerging themes?

    If there are no interesting commits, demonstrate that you completed this section by explaining what happened between the VCCs and the fix.
curated_instructions: |
  If you are manually editing this file, then you are "curating" it. Set the
  entry below to "true" as soon as you start. This will enable additional
  integrity checks on this file to make sure you fill everything out properly.
  If you are a student, we cannot accept your work as finished unless curated is
  set to true.
upvotes_instructions: |
  For the first round, ignore this upvotes number.

  For the second round of reviewing, you will be giving a certain amount of
  upvotes to each vulnerability you see. Your peers will tell you how
  interesting they think this vulnerability is, and you'll add that to the
  upvotes score on your branch.
announced_instructions: |
  Was there a date that this vulnerability was announced to the world? You can
  find this in changelogs, blogs, bug reports, or perhaps the CVE date. A good
  source for this is Chrome's Stable Release Channel
  (https://chromereleases.googleblog.com/).
  Please enter your date in YYYY-MM-DD format.
fixes_vcc_instructions: |
  Please put the commit hash in "commit" below (see my example in
  CVE-2011-3092.yml). Fixes and VCCs follow the same format.
description_instructions: |
  You can get an initial description from the CVE entry on cve.mitre.org. These
  descriptions are a fine start, but they can be kind of jargony.

  Rewrite this description in your own words. Make it interesting and easy to
  read to anyone with some programming experience. We can always pull up the NVD
  description later to get more technical.

  Try to still be specific in your description, but remove Chromium-specific
  stuff. Remove references to versions, specific filenames, and other jargon
  that outsiders to Chromium would not understand. Technology like "regular
  expressions" is fine, and security phrases like "invalid write" are fine to
  keep too.