CVE-2011-2864

CVE: CVE-2011-2864
CWE:
- 119
- 125
bugs:
- 95563
repo: https://chromium.googlesource.com/external/github.com/harfbuzz/harfbuzz/
vccs:
- note: They were adding Harfbuzz to the third_party directory
  commit: 83f6e08f4c56ef411ad1da5f3bfd4711ec94b052
fixes:
- note: 
  commit: b103b5975f6ac1b1b491510b8246091f160d9013
bounty:
  date: 
  amount: 
  references: []
lessons:
  yagni:
    note: 
    applies: false
  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: false
  complex_inputs:
    note: 
    applies: false
  distrust_input:
    note: |
      With a buffer overflow vulnerability, it is crucial to distrust and validate
      input everytime to prevent unexpected data from being processed
    applies: true
  least_privilege:
    note: 
    applies: false
  native_wrappers:
    note: 
    applies: false
  defense_in_depth:
    note: |
      Any third-party software's code might have potential problem to it. It is also
      harder to test. By utilizing some automated tools such as ASAN or ClusterFuzz,
      Google's developers were be able to detect the vulnerability easily and faster
      than manually testing
    applies: true
  secure_by_default:
    note: 
    applies: false
  environment_variables:
    note: 
    applies: false
  security_by_obscurity:
    note: 
    applies: false
  frameworks_are_optional:
    note: 
    applies: false
reviews:
- 7841023
- 7851010
upvotes: 6
mistakes:
  answer: "The coding mistake that was made in a third party software that led to
    index out\nof bound error.\n\nThe coding mistake was made in a piece of third
    party software that led to an \nindex out of bound error. This approach is important
    because it is hard to \ninvestigate and manually debug third-party codebases for
    memory corruption errors."
  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: '2011-09-16'
subsystem:
  name: Harfbuzz
  answer: Based on the bug report's comments and the file location
  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: '2011-09-06'
  answer: "Found by Google's ASAN tool and reproduced by ClusterFuzz tool. AddressSanitizer
    is a \ntesting tool to detect memory corruption. And ClusterFuzz is a distributed
    fuzzing \ninfrastructure to automatically de-duplicate and file reproducible crashes.
    There are \nseveral that people reported the same issue also found by ASAN tool.\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: true
description: "The vulnerability was Google Chrome before 14.0.835.163 in the way the
  \nthird-party software Harfbuzz handles Tibetan characters. \n\nHarfBuzz is a software
  development library for text shaping, which is the process\nof converting Unicode
  text to glyph indices and positions.\n\nThe implementation didn't handle the case
  when the character is out of the Tibetan\ncharacters table's bound. At best, this
  causes a crash. At worst, this kind of \nvulnerability can lead to arbitrary read
  or write operations to be performed on\nunauthorized memory locations as it is a
  \"buffer overflow\".\n\nThis is possible in a Cross-Site Scripting (XSS) scenario.
  An attacker may be able \nto execute arbitrary code or unspecified vectors, alter
  the intended control flow, \nread sensitive information, or cause the system to
  crash.\n"
unit_tested:
  fix: false
  code: true
  answer: |
    Based on the error message on the bug report, there is a TestShell running
    along with the ASAN tool to test the system
  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 two other people, using the same tool, that found the same vulnerability.
    All of the issues were fixed by this fix
  events:
  - date: '2011-09-07'
    name: Issue 95665 and issue 95664 were duplicated
  - 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 the VCC (when the file was first created), there were no commits
    until the\nfix \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.