angler-fishThe Vulnerability History Project

CVE-2007-3847

In HTTPD, which is an open source web server for unix-like systems, remote servers can cause denial of service when using threaded MPM by sending a malicious date header that triggers buffer over-read. Threaded MPM refers to using multi-processing modules that handle tasks such as binding network ports, and accepting requests. The triggered buffer over-read refers to when the code attempts to read adjacent memory beyond the current buffer, where sensitive data could be stored that is not supposed to be accessed.


The date input causing the issue seems to have been trusted without doing all of the proper validation and checking before using it. As mentioned earlier I believe this vulnerability could have been avoided if boundary checks were performed. To prevent vulnerabilities of this kind in the future, each component is supposed to distrust outside inputs and perform the necessary validations to reject bad inputs.
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CVE: CVE-2007-3847
CWE: 126
ipc:
  note: 
  answer: 
  question: |
    Did the feature that this vulnerability affected use inter-process
    communication? IPC includes OS signals, pipes, stdin/stdout, message
    passing, and clipboard. Writing to files that another program in this
    software system reads is another form of IPC.

    Answer should be boolean. Explain your answer
bugs: []
i18n:
  note: 
  answer: 
  instructions: |
    Was the feature impacted by this vulnerability about internationalization
    (i18n)? An internationalization feature is one that enables people from all
    over the world to use the system. This includes translations, locales,
    typography, unicode, or various other features.

    Answer should be boolean. Write a note about how you came to the conclusions
    you did.
repo: 
vccs:
- note: Formerly 13bdffd40b879b52adc435e299411f6d48190d62 before HTTPD rewrote Git
    history.
  commit: f8511d81d82f1981f1ad10529eb4fc7f64253e46
- note: 
  commit: 
fixes:
- note: Formerly afc7b3d09fd01a12cafa3a5e3b9193b91b242afe before HTTPD rewrote Git
    history.
  commit: 139f41aa7533170b66768b53fe0a5717933fc483
- note: 
  commit: 
bounty:
  amt: 
  url: 
  announced: 
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: |
      I believe this vulnerability could have been avoided if bound checking
      was performed. Of course it is more complex than just that but I believe
      the core principle of distrusting input still applies here.
    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: []
upvotes: 3
CWE_note: 
mistakes:
  answer: |
    The date input causing the issue seems to have been trusted without doing
    all of the proper validation and checking before using it. As mentioned
    earlier I believe this vulnerability could have been avoided if boundary
    checks were performed. To prevent vulnerabilities of this kind in the
    future, each component is supposed to distrust outside inputs and perform
    the necessary validations to reject bad inputs.
  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: 
reported: 
announced: '2007-08-01'
published: 
subsystem:
  name: proxy
  answer: Based on the source code files that introduced and fixed the issue.
  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.
discovered:
  date: 
  answer: There were no evidence found on how this vulnerability was discovered
  google: 
  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 this part blank.
  automated: 
description: |
  In HTTPD, which is an open source web server for unix-like systems, remote
  servers can cause denial of service when using threaded MPM by sending a
  malicious date header that triggers buffer over-read. Threaded MPM refers to
  using multi-processing modules that handle tasks such as binding network
  ports, and accepting requests. The triggered buffer over-read refers to when
  the code attempts to read adjacent memory beyond the current buffer, where
  sensitive data could be stored that is not supposed to be accessed.
unit_tested:
  fix: false
  code: false
  answer: |
    From looking at the commits that introduced and fixed the vulnerability,
    there are no evidence that tests of any kind were involved. Both commits
    only changed files in the impacted module, proxy.
  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.
specification:
  answer: 
  answer_note: 
  instructions: |
    Is there mention of a violation of a specification? For example,
    an RFC specification, a protocol specification, or a requirements
    specification.

    Be sure to check all artifacts for this: bug report, security
    advisory, commit message, etc.

    The answer field should be boolean. In answer_note, please explain
    why you come to that conclusion.
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!)
autodiscoverable:
  answer: 
  answer_note: 
  instructions: |
    Is it plausible that a fully automated tool could have discovered
    this? These are tools that require little knowledge of the domain,
     e.g. automatic static analysis, compiler warnings, fuzzers.

    Examples for true answers: SQL injection, XSS, buffer overflow

    Examples for false: RFC violations, permissions issues, anything
    that requires the tool to be "aware" of the project's
    domain-specific requirements.

    The answer field should be boolean. In answer_note, please explain
    why you come to that conclusion.
yaml_instructions: 
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:
  commits:
  - note: |-
      Simply put, I believe the fix performed a complex bound check to protect

      against the buffer over-read caused by the malicious date input. A

      boundary check is where the input is checked in the validation step to

      ensure its validity in terms of length, size, and type and rejecting it

      or handling the case according to the system's requirements when its not

      considered valid.


      Formerly afc7b3d09fd01a12cafa3a5e3b9193b91b242afe before HTTPD rewrote Git history.
    commit: 139f41aa7533170b66768b53fe0a5717933fc483
  - 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?
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.
nickname_instructions: |
  A catchy name for this vulnerability that would draw attention it. If the
  report mentions a nickname, use that. Must be under 30 characters.
  Optional.
reported_instructions: 
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.
published_instructions: 
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.

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