CVE-2014-1723

aka Right to Left to Wrong

CVE: CVE-2014-1723
CWE:
- 20
bugs:
- 337746
repo: 
vccs:
- note: 'These commits added code to the escape characters list, but didn''t add LtR
    or invisible characters

    '
  commit: 8c0af3834e11d643562c13788c06c695f2666f51
- note: 'These commits added code to the escape characters list, but didn''t add LtR
    or invisible characters

    '
  commit: 61197dffa1137d7e4fe003281ad3e38108e90411
fixes:
- note: 'This commit added the logic to check for more characters to escape, such
    as LtR

    '
  commit: 2cd905494ba700a8e2097d614ed39ad36d1519f2
bounty:
  date: '2014-04-08 13:35:00.000000000 -04:00'
  amount: 1500.0
  references:
  - http://chromereleases.googleblog.com/2014/04/stable-channel-update.html
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: I would put this as a complex input, since this character is only used in
      obscure languages
    applies: true
  distrust_input:
    note: |
      Since the vulnerability stems from a core trust of user input, this common lesson applies.
      It shows that we should NEVER trust user input, and instead should try to only allow things
      that we know will be safe for our application. For example, using a whitelist instead of a blacklist.
    applies: true
  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: 
    applies: 
  frameworks_are_optional:
    note: 
    applies: 
reviews:
- 192973004
- 181483008
upvotes: 29
mistakes:
  answer: |
    Personally, I think that requirement mistakes were made that led to this vulnerability. The original
    coders either didn't have knowledge of this character or how it could lead to problems in the future,
    but it eventually came up. Luckily, it was reported by a good samaritan, hopefully before any malicious
    users had the chance to use it against other users.
  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: Right to Left to Wrong
announced: '2014-04-09 06:57:51.277000000 -04:00'
subsystem:
  name: net
  answer: This bug was in the net/base code for chromium, based on the path of the
    file affected
  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: '2014-01-24'
  answer: This vulnerability was discovered by a good samaritan who found it
  google: false
  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: "Malicious actors could insert a right to left (RtL Character) into a
  url using their keyboard to create very misleading urls. The RtL reverses\ncharacters
  after it in a string in the GUI. This character is completely insivible to the users
  of chromium, \nso it was almost impossible to detect. For example, a malicious user
  could use this character and create \na url like \"coolcamsj.png\". However, due
  to the RtL character in the url, the browser would actually read \nthe string as
  \"coolcamgnp.js\" and load that, which has the potential to be malicious javascript.
  \n"
unit_tested:
  fix: true
  code: true
  answer: true
  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 seems that nothing really was happening at the time of this vulnerabilty,
    as\na non-google employee reported the bug. However, it is notable that the original
    \nassignee to the bug was off of work for a couple of weeks when the bug was reported,\nso
    it is possible that this bug was left sitting for longer than possible. It looks\nsomeone
    picked it up soon there after though, since it was high severity.\n"
  events:
  - date: '2014-01-24'
    name: pkasting@chromium.org was out
  - 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: "It seems interesting to me that this bug was not found in the inital pass
      of the code.\nIt seems like a big oversight on the developers part, which didn't
      see how this character could affect code.\nIt also is worth noting that google
      handles bad characters with a blacklist instead of a whitelist. I feel \nlike
      the otherway around would be a better approach.\n"
    commit: 8c0af3834e11d643562c13788c06c695f2666f51
  - 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.