CVE-2015-1243

CVE: CVE-2015-1243
CWE:
- 416
bugs:
- 453279
repo: 
vccs:
- note: Packages and imports are introduced here.
  commit: 91e7e108ecd4ca910a005cb0924e174a8b0e2db3
- note: A huge commit where all the base functionality is introduced.
  commit: 18551dbaecaa6417390f443739e671cca55ab984
fixes:
- note: Fix was done about 3 months after bug was found.
  commit: 8d8f2e1e111607fec4c8aa3885e3f55a0b2fb3f3
bounty:
  date: '2015-07-24'
  amount: 3000.0
  references:
  - http://bugs.chromium.org/p/chromium/issues/detail?id=453279
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: |
      This would be a really easy but to miss because you would assume
      nothing about the object would change from the copy you made. No defensive
      checks were in place to make sure there weren't differences between the
      copy and the original before it was modified.
    applies: true
  secure_by_default:
    note: 
    applies: 
  environment_variables:
    note: 
    applies: 
  security_by_obscurity:
    note: 
    applies: 
  frameworks_are_optional:
    note: 
    applies: 
reviews:
- 1039523003
- 1072773002
upvotes: 
mistakes:
  answer: |
    The coding mistake was made when this code was first created. This code was
    not modifed again until this bug was found. The time between the bug being
    found, the cause of the bug and the possible fix was very short (less then a
    day).
    This was a simple mistake where the coders assumed that the object they
    made a copy of couldn't be changed and would remain identical to their
    copy.
    This mistake was mostly a coding mistake. The coders made an assumption
    about the state of their object, and that assumption ended up being
    incorrect, which resulted in this vulnerability.
    The reviewers likely looked over this code and thought along the same lines
    as the code author. There were not any unit tests to check for this part of
    the code behavior, they were added after the defensive check was put into
    place as no one anticipated this would be an issue.
  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: '2015-05-01 06:59:05.043000000 -04:00'
subsystem:
  name: dom
  answer: See the description and the CVE
  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: '2015-01-29'
  answer: |
    Automated unit tests were not involved in finding this vulnerability. It
    appears to have been found by a regular chrome user whose email is
    saif.els...@gmail.com who then filed a bug report.
  google: false
  contest: 
  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: |
  When Google first wrote it's DOM implementation the "use-after-free"
  vulnerability was intoduced. They iterated over a copy of a structure in
  an Observer class and never checked the conditions of the original before
  attempting to use it based on the copy. This caused the tab being used to
  crash.
  This could allow for a Denial of Service attack or other unspecified impact
  because a remote attacker can trigger this by trying to force the freeing
  of a non registered observer.
  This also becomes a data integrity issue as the memory that was freed
  may have been allocated again somewhere else, causing corruption of that
  data.
unit_tested:
  fix: true
  code: true
  answer: |
    This code was tested but the tests did not catch the vulnerability. After
    the code was fixed, new unit tests were created.
  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: There were no major events during the history of this vulnerability.
  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: 
  commits:
  - 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.