________________________________________________________________________
From the low-hanging-fruit-department
Kaspersky Generic Malformed Archive Bypass (ZIP Compressed Size)
________________________________________________________________________
Release mode : Coordinated Disclosure
Ref : [TZO-05-2020] - Kaspersky Generic Archive Bypass (ZIP
Compressed Size)
Vendor : Kaspersky
Status : Patched
CVE : Unknown
Dislosure Policy: https://caravelahq.com/b/policy/20949
Blog : https://blog.zoller.lu
Vendor Advisory :
https://support.kaspersky.com/general/vulnerability.aspx?el=12430#021219
Affected Products
=================
List of affected products
The issue affected Secure Connection product and consumer products in
those it is incorporated:
Kaspersky Secure Connection prior to version 4.0 (2020) patch E.
Kaspersky Internet Security prior to version 2020 patch E.
Kaspersky Total Security prior to version 2020 patch E.
Kaspersky Security Cloud prior to version 2020 patch E.
Fixed versions
Kaspersky Secure Connection 4.0 (2020) patch E.
Kaspersky Internet Security 2020 patch E.
Kaspersky Total Security 2020 patch E.
Kaspersky Security Cloud 2020 patch E.
I. Background
----------------------------
Kaspersky Lab is a multinational cybersecurity and anti-virus provider
headquartered in Moscow, Russia and operated by a holding company in the
United Kingdom. It was founded in 1997 . Kaspersky Lab develops and
sells antivirus, internet security, password management, endpoint
security, and other cybersecurity
products and services.
II. Description
----------------------------
The parsing engine supports the ZIP archive format. The parsing engine
can be bypassed by specifically manipulating an ZIP Archive
(Compression Size Flag) so that it can be accessed by an end-user but
not the Anti-Virus software. The AV engine is unable to scan the
container and gives the file a "clean" rating.
I may release further details after all known vulnerable vendors have
patched their engines.
III. Impact
----------------------------
Impacts depends on the contextual use of the product and engine within
the organisation of a customer. Gateway Products (Email, HTTP Proxy etc)
may allow the file through unscanned and give it a clean bill of health.
Server side AV software will not be able to discover any code or sample
contained within this ISO file and it will not raise suspicion even if
you know exactly what you are looking for (Which is for example great to
hide your implants or Exfiltration/Pivot Server).
There is a lot more to be said about this bug class, so rather than bore
you with it in
this advisory I provide a link to my 2009 blog post
http://blog.zoller.lu/2009/04/case-for-av-bypassesevasions.html
IV. Patch / Advisory
----------------------------
Update to the respective available versions as found at
https://support.kaspersky.com/general/vulnerability.aspx?el=12430#021219
Thanks to Kaspersky for coordinating this vulnerability.
