CVE-2010-3248

aka Clippy's Revenge

CVE: CVE-2010-3248
CWE: 
bugs:
- 41654
repo: 
vccs:
- note: 
  commit: 98b5bcbd5136888ee6a6d63b5e2d69c85865a86a
fixes:
- note: This bug was resolved in one commit by adding several tests to restrict illegal
    access to the clipboard
  commit: 98b5bcbd5136888ee6a6d63b5e2d69c85865a86a
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: 
    applies: 
  secure_by_default:
    note: 
    applies: 
  environment_variables:
    note: 
    applies: 
  security_by_obscurity:
    note: |
      It's reasonable to assume that you couldn't access the clipboard outside of
      clipboard events. To discover this vulnerability would require someone with
      an intimate knowledge of the system and/or someone who is incredibly creative.
    applies: true
  frameworks_are_optional:
    note: 
    applies: 
  inter_process_communication:
    note: 
    applies: true
reviews:
- 1815005
upvotes: 16
mistakes:
  answer: |
    This bug was not present in Opera or Firefox, so it was a reasonable assumption that
    someone couldn't access the clipboard outside dedicated clipboard events. This is one
    of those important but very obscure vulnerabilities that are hard to actively defend against.
    The only way to prevent these kind of vulnerabilities, would to be paranoid about every feature
    and have unit tests out the whazoo. While testing your code into the ground is a good way to
    ensure it's safety, I'd say it wouldn't be economical ( or sane ) to write software like this.
  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
nickname: Clippy's Revenge
announced: '2010-09-07 14:00:02.557000000 -04:00'
subsystem:
  name: webkit
  answer: webkit
  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: '2010-04-15'
  answer: Found by a google employee who found this vulnerability by 'adding an IFrame
    containing a text input element into the document, and turning its design-mode
    / content-editable on'
  google: true
  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: |
  A bug was found in chrome which did not retrict javascript from copying to the
  clipboard from any context ( anywhere you can run JavaScript). The person who found the vulnerability,
  wrote an exploit that would hijack the clipboard and constantly set the clipboard to
  a malicious url.

  Here's how his exploit works. First, you start off by creating an invisible iframe element
  in the background and turning the design-mode/content-editable on. This gives the iframe
  access to the "execCommand" in JS, which has a "copy" function which copies the current
  selected content to the clipboard. The attacker can take advantage of this by adding and setting
  a text element inside the iframe to a malicious url and then calling the focus(), select()
  and finally the execCommand()'s copy function to copy to the clipboard. In his exploit,
  he used setTimeout() to make an infinite recursive call on a function which would copy
  his malicious url to the clipboard every 500ms.

  Here's a link to the custom exploit: https://bugs.chromium.org/p/chromium/issues/attachmentText?aid=118061
unit_tested:
  fix: false
  code: false
  answer: |
    There were no automated tests to prevent this before it was discovered.
    After this bug was patched the following day, two other test files were modified
    with additional tests.
      1.) trunk/src/webkit/tools/test_shell/layout_test_controller.cc
      2.) trunk/src/webkit/tools/test_shell/test_shell.cc
  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: |
    The Dev team must have been busy, but there are no comments until the fix was
    completed 2.5 weeks later. It appears that other issues were merged into this
    one as well.
  events:
  - date: '2010-04-15'
    name: Bug Reported
  - date: '2010-05-04'
    name: Bug Fixed
  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: 0
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: |
      There was no single commit which introduced the vulnerability to the system.
      Rather, the vulnerability always existed ( due to a lack of edge case testing )
      until it was discovered and patched. The commit mentioned above, is the first
      commit we see referencing this bug.
    commit: 54452e7b9480332f1e7740540eb7c8824a1071ab
  - 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.