CVE-2011-1439

CVE: CVE-2011-1439
CWE:
- 267
bugs:
- 74763
repo: 
vccs:
- note: |
    This was the commit that changed to the version of breakpad that
    ultimately had to be fixed.
  commit: 167b5f97efe2e9fc2eda0edc04f9a51dd5fc359e
fixes:
- note: "It appears this is just a dependency update to the version of breakpad\nthat
    fixed the functionality that exposed process IDs and enabled\nthis vulnerability.
    \n"
  commit: e3e4598b72a114e5711b4acb6f534eac274736d1
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: |
      Part of the mitigation of this vulnerability was altering the way that
      input signals were handled to reflect different standards of trust.
    applies: true
  least_privilege:
    note: "This vulnerability existed because the principle of least privlege was
      \nnot properly implemented. Sandboxed applications could access privleges\nthat
      they were not meant to.\n"
    applies: true
  native_wrappers:
    note: 
    applies: 
  defense_in_depth:
    note: |
      Ultimately the mitigation for this vulnerability involved multiple layers
      of fixes in how crash reporting worked, process ids got handles, and signals
      got passed. These fixes all patched seperate parts of the system to make the
      whole more secure.
    applies: true
  secure_by_default:
    note: 
    applies: 
  environment_variables:
    note: 
    applies: 
  security_by_obscurity:
    note: 
    applies: 
  frameworks_are_optional:
    note: 
    applies: 
reviews:
- 6719018
upvotes: 
mistakes:
  answer: |-
    This vulnerability seems to be an issue of design mistakes and maintainability. It appears that the design of the renderer and breakpad functionality did not properly account for the sandboxing that was supposed to happen between processes. The intention to make the processes secure was clearly there, but the follow through was lacking.
    The maintainability aspect of the mistake comes in that a large part of this vulnerability was interaction with the external libraries and dependencies, like breakpad or the Linux kernal signals. As these dependencies evolved, the code was not upkept. In the bug reports the team mentions that a lack of signal verifiability stems directly from failure to amend the code when new features were added.
    This vulnerability falls squarely under the CWE-265 category - Privelege/Sandbox Issues. This vulnerability closely aligns with CWE-250 - Execution with Unnecessary Priveleges. The vulnerability was caused by unnessary exposure of process IDs, which led to conditions where a sandboxed process could unsafely execute code and break it's sandbox. Another CWE which it relates to is 267 - Privelege Defined With Unsafe Actions. In this vulnerability code used it's privleges improperly and unsafely exposed process IDs. A mitigation mentioned for 267 is to explicitly manage trust zones in the software, which appears to be the route Google took here.
  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: '2011-04-27'
subsystem:
  name: renderer
  answer: |
    It appears that the vector for attack is initially through the renderer,
    but there was also vulnerable functionality in the crash reporting subsystem,
    and in the methodology by which different subsystems pass messages.
  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: '2011-03-03'
  answer: "The chrome security team originally found this vulnerability when exploring
    the way\nthat the Chrome Sync feature works with Chrome extensions. \n"
  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 vulnerability is related to incomplete sandboxing around the chrome\nrenderer
  process and chrome extensions. By tracing process ids and messages\nit would be
  possible for an attacker to spoof parts of chrome and execute\narbitrary code.\n\nThe
  vulnerability did not effect Windows, but on Linux it was possible for\nattackers
  to escape their sandbox and install their own extensions remotely.\nThis is Linux
  specific because on Linux it was possible for sandboxed processes\nto interfere
  with each other due to requirements for chrome's crash reporting\nsystem, breakpad.
  \n\nIt is unclear in the chrome bug reporting whether the vector of attack was\ndirectly
  through breakpad, but the interprocess communication with breakpad\nallows for improper
  information disclosure of process IDs. This is what\nexposes the system to spoofing.\n"
unit_tested:
  fix: false
  code: false
  answer: |
    It appears unit testing was not involved in this vulnerability. The vulnerability
    was detected through manually exploring and reviewing functionality, not
    via an automated process.
  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: |
    It appears that a major event was when the breakpad team stabilized breakpad
    and the security team could roll to the correct version of breakpad. The
    security team had identified that the vulnerability could not be fully
    patched without this breakpad update, so they seemed to be waiting on the
    proper changes to be stable in breakpad. It is unclear how much communication
    there was between the chrome security people and breakpad people.
  events:
  - date: '2011-03-30'
    name: Breakpad released and stable
  - 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: "The actual code in question being a dependency configuration file,\nthe
    commits don't seem interesting in the context of this vulnerability.\nThe commits
    are usually just rollbacks or updates of depency paths. The \nmost interesting
    thing about it is that frequency of commits: the file changes\nmultiple times
    a day, being altered by multiple users.\n"
  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.