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Oh, I Found a
Security Issue
#DjangoCPH 2018 • @m_holtermann
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I’m Markus Holtermann
@m_holtermann • github.com/MarkusH • markusholtermann.eu
@laterpay • laterpay.net
• Django Core Developer
• Software Engineer at
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Date: Tue, 4 Apr 2017 08:31:25 -0700 (PDT)
From: Tim Graham <*****@gmail.com>
To: django-announce
Subject: [django-announce] Django security releases issued: 1.10.7,
1.9.13, and 1.8.18
Today the Django team issued 1.10.7, 1.9.13, and 1.8.18 as part of our
security process. These releases address two security issues, and we
encourage all users to upgrade as soon as possible:
https://www.djangoproject.com/weblog/2017/apr/04/security-releases/
As a reminder, we ask that potential security issues be reported via
private email to security@djangoproject.com and not via Django's Trac
instance or the django-developers list. Please see
https://www.djangoproject.com/security for further information.
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Django’s Security
Policy
https://docs.djangoproject.com/en/dev/internals/security/
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Django’s Security
Report & Release
Process
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Report to
security@djangoproject.com
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Assessing the reported issue
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Fixing the issue
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Confirming the fix
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Pre-notification
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Release
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Announcement
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Bounty
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How to apply this?
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● Setup reporting channel
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● Setup reporting channel
● Monitor reporting channel
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● Setup reporting channel
● Monitor reporting channel
● Fix the issue
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● Setup reporting channel
● Monitor reporting channel
● Fix the issue
● Release & Announce
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● Setup reporting channel
● Monitor reporting channel
● Fix the issue
● Release & Announce
● Learn from it
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Django’s History
https://docs.djangoproject.com/en/dev/releases/security/
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Reassuringly secure.
Django takes security seriously and
helps developers avoid many
common security mistakes.
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Number of CVEs per year
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CVEs per classification
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XSS
Cross Site Scripting
var json = {{ data|json.dumps|safe }};
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var json = JSON.parse(“{{ data | escapejs }}”);
https://code.djangoproject.com/ticket/17419
Avoiding XSS
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In your .js file (with jQuery)
$(‘#json2’).data(‘foo’)
https://code.djangoproject.com/ticket/17419
Avoiding XSS
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CSRF
Cross Site Request Forgery
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DoS
Denial of Service
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Unvalidated Redirects
http://yoursite.eu/login?next=mysite.eu
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Header Poisoning
POST /password_reset/ HTTP/1.1
Host: somethingevil.com
Content-Type: …urlencoded
email=your_email&action=reset
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RCE
Remote Code Execution
pickle.loads("cposix\nsystem\np0\n(S'ls'…")
exec/eval
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Authentication/Authorization
Failure
@login_required()
def delete_user(request, uid):
User.objects.filter(id=uid).delete()
return redirect(‘index’)
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Directory Traversal
os.path.join(MEDIA_ROOT, “../../settings.py”)
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Information Leakage
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OWASP Top 10
https://www.owasp.org/
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Thank you!
Also thanks to @fapolloner
who helped me prep this talk
@m_holtermann
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