CVE-2013-2879

CVE: CVE-2013-2879
CWE:
- 79
- 200
bugs:
- 252062
repo: 
vccs:
- note: commit was removing sign in flow that Chrome no longer supported, added in
    poor signin flow logic.
  commit: 3c372a1ae0e609691994bc74ade55175a3e2ea97
fixes:
- note: ''
  commit: ada3419d945560713e1dc6b9a9feb8dfeefc942b
bounty:
  date: '2013-07-09 12:00:00.000000000 -04:00'
  amount: 10750.0
  references:
  - http://chromereleases.googleblog.com/2013/07/stable-channel-update.html
lessons:
  yagni:
    note: A lot of code was removed in the VCC, causing the vulnerability to appear.
      In the Fix commit, code was only added and not removed. This goes along with
      the yagni principle of not adding extra code that is not needed by removing
      code and adding code only when needed.
    applies: true
  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: The problem came from a trust issue between two processes, and the fix was
      to sever the trust between the processes. Remembering to distrust input by default
      is a good strategy to avoid vulnerabilities like this one.
    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:
- 17797002
- 18178003
- 17836005
- 17844005
- 17808002
- 17482002
- 17962003
- 17727002
- 19544006
- 18139005
- 19919007
- 17809002
upvotes: 9
mistakes:
  answer: |-
    The basis of this vulnerability was trust. When the file was changed to no longer support non web-based signin flow, certain trusts were not verified, leading to a trust between the sign-in process and the renderer process that opened up the subsystem to threats. Trust boundaries are important and should be reviewed when doing things like removing features.
    The vulnerability was not found on a single or small set of lines, but rather within the overall design of the subsystem after the non web-based signin flow was removed. The fix involved removing very few lines and instead adding in the new logic that was needed after the loss of the previous feature. While a design may be fine before, this shows that it is good to re-verify a design after removing a decently sized feature.
  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: '2013-07-10 06:55:02.337000000 -04:00'
subsystem:
  name: signin
  answer: Looking at the directory of the files that were modified in the fix commit,
    the subsytem was the signin 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: '2013-06-20'
  answer: The vulnerability was reported by Andrey Labunets, who lays out the problem
    with step by step descriptions of what needs to happen for an attack to use their
    vulnerability. He talks about his exploit chain that automates the reproduction
    of the vulnerability. He does not talk about whether this vulnerability was found
    via an automated test, but I am setting automated to true since he has the repoduction
    of it automated.
  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: true
description: |-
  This vulnerability occurs in a user signin process, where a user can be tricked into signing into an attacker's account, via Cross-Site Scripting, effectively phishing. This can cause the user's personal information to be revealed to the attacker. The attacker can then force an account sync with the victim, giving the attacker the ability to run code under the victim's privilege.
  The vulnerability stems from the trust that the sign-in process has with the renderer process. There was trust between these two processes at points that the trust could be used against them in an attack.
unit_tested:
  fix: false
  code: true
  answer: From looking around the code in the fix commit, it does not seem that unit
    tests were changed. From looking at the VCC commit though, there were unit test
    files that were modified, and these files looked to be used to test the signin
    subsystem.
  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: As the VCC happened on June 7th and the fix happened on June 26th, there
    wasn't much time between them. As such, there were no major events that I can
    recognize between them.
  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 looking through the commits using the command git log 3c372a1ae0e60..ada3419d945560713e1dc6b9a9feb8dfeefc942b
    -- chrome/browser/signin/signin_browsertest.cc there were no commits that stood
    out as having something to do with the signin subsystem or any problems like this
    vulnerability. Due to the time difference between the two commits, very few other
    commits happened at the time, and those that existed didn't seem to pertain to
    the vulnerability.
  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.