CVE-2021-43975

aka Small RPC Buffer, Big Input

CVE: CVE-2021-43975
CWE:
- '787'
ipc:
  note: |
    RPC is a form of inter-process communication there force since the amount of memory
    exceeded the amount the RPC can handle then that means the vulnerability did affected the
    use of inter-process communication
  answer: true
  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 must be true or false.
    Write a note about how you came to the conclusions you did, regardless of
    what your answer was.
CVSS: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
bugs:
- 2024989
i18n:
  note: "If data was passed in that fit the character requirements for input but contained\nmany
    diacritics and ligatures which added to the amount of bytes incorrectly allocated
    \nfor a slab of memory.\n"
  answer: true
  question: |
    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 true or false
    Write a note about how you came to the conclusions you did, regardless of
    what your answer was.
vccs:
- note: Discovered automatically by archeogit.
  commit: 98c4c20142e985faeb693d8546e53d2ff7eebe26
- note: Discovered automatically by archeogit.
  commit: e7b5f97e6574dc4918e375d5f8d24ec31653cd6d
- note: Discovered automatically by archeogit.
  commit: 1a713f87a0914ccaa9532e61ee73ac691c1f9e3d
fixes:
- note: "The fix implements range bound checking for the slab (the amount of memory
    being allocated) \nthat is coming in it checks the length of such data and if
    it less than what a RPC can handle \nthen it does error handling.\n"
  commit: b922f622592af76b57cbc566eaeccda0b31a3496
vouch:
  note: There was no mention of it in the pull request, commit message or bug report
  answer: false
  question: |
    Was there any part of the fix that involved one person vouching for
    another's work?

    This can include:
      * signing off on a commit message
      * mentioning a discussion with a colleague checking the work
      * upvoting a solution on a pull request

    Answer must be true or false.
    Write a note about how you came to the conclusions you did, regardless of what your answer was.
bounty:
  amt: 
  url: 
  announced: 
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: Complex inputs can lead to memory overflow issues.
    applies: true
  distrust_input:
    note: The input leads to the memory overflow so we need to handle such input
    applies: true
  least_privilege:
    note: |
      Since an attacker can modify data using this vulnerability referenced in the link above
      then they can gain certain privileges by sending specific packets through a device
    applies: true
  native_wrappers:
    note: 
    applies: false
  defense_in_depth:
    note: |
      It is stated in https://security.netapp.com/advisory/ntap-20211210-0001/
      That this vulnerability can lead to information disclosure so we need protections
      and layers to prevent that data being leaked.
    applies: true
  secure_by_default:
    note: 
    applies: false
  environment_variables:
    note: 
    applies: false
  security_by_obscurity:
    note: "Someone may not send certain input for a while which gives the impression
      that the \nsystem is fine but if someone sends incorrect input then RPC can't
      effectively make \na correct call.\n"
    applies: true
  frameworks_are_optional:
    note: 
    applies: false
reviews: []
sandbox:
  note: |
    This is a sandboxing issue because a hacker can develop a script or pass in characters
    that will lead to a overextension of the buffer causing an overflow in memory. So a threat would
    pass through this vulnerability
  answer: true
  question: |
    Did this vulnerability violate a sandboxing feature that the system
    provides?

    A sandboxing feature is one that allows files, users, or other features
    limited access. Vulnerabilities that violate sandboxes are usually based on
    access control, checking privileges incorrectly, path traversal, and the
    like.

    Answer should be true or false
    Write a note about how you came to the conclusions you did, regardless of
    what your answer was.
upvotes: 3
CWE_note: Manually Confirmed
mistakes:
  answer: "This would be categorized as a lapse mistake based on the fact that a forgotten
    \nconditional was added to the block to check found boundness which is a simple
    coding mistake\nthat couldn't be found without actual fuzzing it or testing it
    through a virtual machine\nwith digital devices. It's hard to test devices based
    on these conditionals so it makes sense\nto why we would have this kind of error.
    A proper mitigation to do is to check the length\nof a buffer to the length of
    the data being passed in so one doesn't have this buffer over flow issue.\n"
  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?

    There can, and usually are, many mistakes behind a vulnerability.

    Remember that mistakes can come in many forms:
    * slip: failing to complete a properly planned step due to inattention
              e.g. wrong key in the ignition
              e.g. using < instead of <=
    * lapse: failing to complete a properly planned step due to memory failure
              e.g. forgetting to put car in reverse before backing up
              e.g. forgetting to check null
    * planning error: error that occurs when the plan is inadequate
              e.g. getting stuck in traffic because you didn't consider the
                   impact of the bridge closing
              e.g. calling the wrong method
              e.g. using a poor design

    These are grey areas, of course. But do your best to analyze the mistakes
    according to this framework.

    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?

    Write a thoughtful entry here that people in the software engineering
    industry would find interesting.
nickname: Small RPC Buffer, Big Input
subsystem:
  name: hw_atl
  note: The device driver for aquantia atlantic devices known as the hw_atl directory
  question: |
    What subsystems was the mistake in? These are WITHIN linux kernel

    Determining the subsystem is a subjective task. This is to help us group
     similar vulnerabilities, so choose a subsystem that other vulnerabilities would be in. Y

    Some areas to look for pertinent information:
      - Bug labels
      - Directory names
      - How developers refer to an area of the system in comments,
        commit messages, etc.

    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.

    Example linux kernel subsystems are:
      * drivers
      * crypto
      * fs
      * net
      * lib

    Name should be:
      * all lowercase English letters
      * NOT a specific file
      * can have digits, and _-@/

    Can be multiple subsystems involved, in which case you can make it an array
    e.g.
        name: ["subsystemA", "subsystemB"] # ok
        name: subsystemA # also ok
discovered:
  answer: "Date Discovered: 2021-11-15 1402:22 +0000\nIt was found automatically when
    running a tests through a fuzzer. The vulnerability was discovered \nby a PHD
    student at NYU and was fixed by an employee at RedHat which IBM owns so no GOOGLE
    employees were\non this project.\n"
  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, contest, and developer flags can be true, false, or nil.

    If there is no evidence as to how this vulnerability was found, then please
    explain where you looked.
  automated: true
  developer: true
discussion:
  note: |
    There was no discussion between other commits, commits on this file are few and far between
    and the commit fix statement gave more of explanation of the fix rather than a discussion which
    was completed in a period of 2 days since discovery of the vulnerability by fuzzing
  question: |
    Was there any discussion surrounding this?

    A discussion can include debates, disputes, or polite talk about how to
    resolve uncertainty.

    Example include:
      * Is this out of our scope?
      * Is this a security?
      * How should we fix this?

    Just because you see multiple comments doesn't mean it's a discussion.
    For example:
      * "Fix line 10". "Ok" is not what we call a discussion
      * "Ping" (reminding people)

    Check the bugs reports, pull requests, and mailing lists archives.

    These answers should be boolean.
      discussed_as_security: true or false
      any_discussion: true or false

    Put any links to disagreements you found in the notes section, or any other
    comment you want to make.
  any_discussion: false
  discussed_as_security: false
stacktrace:
  note: "The developer who fix this bug only put the resulting stacktrace log derived
    \nfrom his fuzzer into the bug report there was no indication of a fixed stack
    trace.\n"
  question: |
    Are there any stacktraces in the bug reports?

    Secondly, if there is a stacktrace, is the fix in the same file that the
    stacktrace points to?

    If there are no stacktraces, then both of these are false - but be sure to
    mention where you checked in the note.

    Answer must be true or false.
    Write a note about how you came to the conclusions you did, regardless of
    what your answer was.
  any_stacktraces: true
  stacktrace_with_fix: false
description: "The method (hw_atl_utils_fw_rpc_wait) that was the source of the vulnerability
  had the intended functionality \nof polling address from other ethernet devices
  receiving data derived from it to execute RPCs\n(Remote Procedure Calls) which executes
  a program in a particular address of memory. It was found that someone \ncould manipulate
  the packets being sent over a network to cause a buffer overflow when the data being
  sent \nexceeds available memory this could lead for the procedure from not being
  executed leading to a denial of\nservice from prevent the execution of some arbitrary
  function.\n"
unit_tested:
  fix: false
  code: false
  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 code: and fix: - your answer should be boolean.

    For the code_answer below, look not only at the fix but the surrounding
    code near the fix in related directories and determine if and was there were
    unit tests involved for this subsystem.

    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.
  fix_answer: |
    Unit tests not found in codebase https://github.com/torvalds/linux/search?q=hw_atl_utils_fw_rpc_wait&type=code.
    But in the bug report it indicates that tests were ran in a QEMU emulator (Quick Emulator).
  code_answer: |
    Unit tests not found in codebase https://github.com/torvalds/linux/search?q=hw_atl_utils_fw_rpc_wait&type=code.
    But in the bug report it indicates that tests were ran in a QEMU emulator (Quick Emulator).
reported_date: '2021-11-13'
specification:
  note: A requirement is to validate the amount of memory allocated for RPC which
    was not met.
  answer: true
  instructions: |
    Is there mention of a violation of a specification? For example, the POSIX
    spec, an RFC spec, a network protocol spec, or some other requirements
    specification.

    Be sure to check the following artifacts for this:
      * bug reports
      * security advisories
      * commit message
      * mailing lists
      * anything else

    The answer field should be boolean. In answer_note, please explain
    why you come to that conclusion.
announced_date: '2021-11-17'
curation_level: 2
published_date: '2021-11-17'
forgotten_check:
  note: |
    This is because the fix commit adds a conditional that checks the length of the data
    being passed by the device to prevent the memory buffer overflow issue.
  answer: true
  question: |
    Does the fix for the vulnerability involve adding a forgotten check?

    A "forgotten check" can mean many things. It often manifests as the fix
    inserting an entire if-statement or a conditional to an existing
    if-statement. Or a call to a method that checks something.

    Example of checks can include:
      * null pointer checks
      * check the current role, e.g. root
      * boundary checks for a number
      * consult file permissions
      * check a return value

    Answer must be true or false.
    Write a note about how you came to the conclusions you did, regardless of
    what your answer was.
CWE_instructions: |
  Please go to http://cwe.mitre.org and find the most specific, appropriate CWE
  entry that describes your vulnerability. We recommend going to
  https://cwe.mitre.org/data/definitions/699.html for the Software Development
  view of the vulnerabilities. We also recommend the tool
  http://www.cwevis.org/viz to help see how the classifications work.

  If you have anything to note about why you classified it this way, write
  something in CWE_note. This field is optional.

  Just the number here is fine. No need for name or CWE prefix. If more than one
  apply here, then place them in an array like this
    CWE: ["123", "456"] # this is ok
    CWE: [123, 456]     # also ok
    CWE: 123            # also ok
autodiscoverable:
  note: "Even though this is a RFC violation in the commit report it is explicitly\nstated
    that the there is an attached log found by fuzzing. Which was able to find \na
    slab-out-of-bounds buffer overflow.\n"
  answer: true
  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

    In systemd, the actually use OZZ Fuzz. If there's a link to it, add it here.

    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.
vcc_instructions: |
  The vulnerability-contributing commits.

  These are found by our tools by traversing the Git Blame history, where we
  determine which commit(s) introduced the functionality.

  Look up these VCC commits and verify that they are not simple refactorings,
  and that they are, in fact introducing the vulnerability into the system.
  Often, introducing the file or function is where the VCC is, but VCCs can be
  anything.

  Place any notes you would like to make in the notes field.
bugs_instructions: |
  What bugs are involved in this vulnerability?

  Please list bug IDs to https://bugzilla.kernel.org/

  Bug ID's can appear in several places:
    * Mentioned in commit messages
    * Mentioned in mailing list discussions
    * References from NVD entry
    * Various other places
yaml_instructions: |
  =================
  ===YAML Primer===
  =================
  This is a dictionary data structure, akin to JSON.
  Everything before a colon is a key, and the values here are usually strings
  For one-line strings, you can just use quotes after the colon
  For multi-line strings, as we do for our instructions, you put a | and then
  indent by two spaces

  For readability, we hard-wrap multi-line strings at 80 characters. This is
  not required, but appreciated.
fixes_instructions: |
  Please put the commit hash in "commit" below.

  This must be a git commit hash from the systemd source repo, a  40-character
  hexademical string/

  Place any notes you would like to make in the notes field.
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: |
      There was a calculation when polling address that caused an infinite loop when they
      disappear from the bus where data is being aggregated to be used in an RPC.
    commit: e7b5f97e6574dc4918e375d5f8d24ec31653cd6d
  question: |
    Are there any interesting commits between your VCC(s) and fix(es)?

    Use this to specify any commits you think are notable in some way, and
    explain why in the note.

    Example interesting commits:
      * Mentioned as a problematic commit in the past
        e.g. "This fixes regression in commit xys"
      * A significant rewrite in the git history
      * Other commits that fixed a similar issue as this vulnerability
      * Anything else you find interesting.
order_of_operations:
  note: The only change added was a conditional statement so this factor doesn't apply
  answer: false
  question: |
    Does the fix for the vulnerability involve correcting an order of
    operations?

    This means the fix involves moving code around or changing the order of
    how things are done.

    Answer must be true or false.
    Write a note about how you came to the conclusions you did, regardless of
    what your answer was.
curated_instructions: |
  If you are manually editing this file, then you are "curating" it.

  Set the version number that you were given in your instructions.

  This will enable additional editorial 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 properly updated.
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: |
  What date was the vulnerability reported to the security team? Look at the
  security bulletins and bug reports. It is not necessarily the same day that
  the CVE was created.  Leave blank if no date is given.

  Please enter your date in YYYY-MM-DD format.
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.

  This is not the same as published date in the NVD - that is below.

  Please enter your date in YYYY-MM-DD format.
published_instructions: |
  Is there a published fix or patch date for this vulnerability?
  Please enter your date in YYYY-MM-DD 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 project-specific
  stuff. Remove references to versions, specific filenames, and other jargon
  that outsiders to this project would not understand. Technology like "regular
  expressions" is fine, and security phrases like "invalid write" are fine to
  keep too.

  Your target audience is people just like you before you took any course in
  security