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Exploit Code Released for a Critical Flaw in Linux Kernel eBPF on Ubuntu Machines

 

Cybersecurity researcher Manfred Paul revealed the details of the code for abusing a critical flaw in the Linux eBPF (Extended Berkeley Packet Filter) kernel on Ubuntu devices. Tracked as CVE-2021-3490, this is a high-severity vulnerability that allows local attackers to exploit Ubuntu devices with relative ease. 

eBPF is a kernel technology that allows user-supplied programs to operate without having to alter the kernel source code or adding additional modules. In other words, this is a lightweight virtual machine within the Linux kernel where programmers can run BPF bytecode that takes advantage of specific kernel resources.

The flaw was disclosed in May by Manfred Paul of the RedRocket CTF team and Trend Micro Zero Day Initiative (ZDI). The issue consists of the fact that user-supplied programs do not go through a proper validation process before they’re executed. If properly exploited, a local attacker could get kernel privileges to run arbitrary code on the machine. 

Valentina Palmiotti, a security researcher at Grapl, explained the technical details of this flaw and its exploitation on Ubuntu short-term releases 20.10 (Groovy Gorilla) and 21.04 (Hirsute Hippo). The researcher created a proof-of-concept exploit code for CVE-2021-3490 and published it on GitHub.

Palmiotti published the report this week which covers the specifics for triggering the bug to leverage it for elevated privileges and to create a denial-of-service (DoS) condition on the target system by locking up all available kernel threads.

Earlier this year, Microsoft announced a new open-source job referred to as ebpf-for-windows that allows developers to make use of the eBPF innovation on leading of Windows. This would certainly be actually attained through incorporating a being compatible coating for existing eBPF projects so they may operate as submodules in Windows 10 and also Windows Server. 

Porting eBPF to Windows is still an early job with a lot of development ahead of it. Palmiotti’s research on CVE-2021-3490 was limited to Linux implementation. 

Microsoft designed the PoC for Groovy Gorilla kernels 5.8.0-25.26 through 5.8.0-52.58, and Hirsute Hippo kernel version 5.11.0-16.17. Patches were actually launched for each Ubuntu model.

HACKED- Windows 10, macOS, Adobe, VMware, Apple and Oracle at The Pwn2Own 2020!


Pwn2Own is a well-known computer hacking contest which is held once every year at the CanSecWest security conference. In this contest, the contestants are tested on how well they could exploit commonly used software and mobile devices with formerly unheard of vulnerabilities.

An issue as grave as the Coronavirus pandemic has clearly not affected the spirits of the Pwn2Own 2020 hacking competition which got done with its first two days.

On Day 1, security researchers and participants bagged a handsome amount of over $180,000 for exploiting the Windows 10, Ubuntu Desktop and macOS, mention sources.

Reportedly, a “team from the Georgia Tech Systems Software and Security Lab succeeded in exploiting a kernel privilege escalation to execute code on macOS” by way of Safari. The attack mechanism that ended up winning for the team $70,000 was comprised of 6 vulnerabilities.

Per the event page (thezdi.com), Georgia Tech employed a “6 bug chain to pop calc and escalate to root”.

The team that has won several preceding editions of the hacking contest, Team Fluoroacetate, won themselves a victorious $40,000 after they employed a “local privilege escalation exploit” meant for the Windows 10.

Reports mention that one of the two members of the aforementioned team also won himself a smashing amount of $40,000 for yet another privilege escalation exploit pursuing Windows 10.

As per sources, the RedRocket CTF team got themselves a win, owing to it to one of their members, Mafred Paul, who bagged an attractive amount of $30,000 for a local privilege escalation exploit focused on Ubuntu Desktop. The hack was about the manipulation of the ‘Input validation bug’.

On Day 2, The Fluoroacetate successfully targeted the Adobe Reader with a local privilege escalation by employing a pair of UAFs, mentioned sources and grabbed an amount of $50,000.

Per reports, the Synacktiv team targeted the VMware Workstation but unfortunately to no avail in the given duration of time. There also were special demonstrations of the Zero Day Initiative against the Oracle VirtualBox.

This was the very first time the organizers allowed “conditional remote participation” in the Pwn2Own hacking contest, understandably because of the increased concerns of people about traveling due to the Coronavirus outbreak.



Ubuntu security advisory to fix the Critical vulnerabilities in Ghostscript


Ubuntu released security advisory to fix the Critical vulnerabilities in Ghostscript.
Ghostscript could be made to crash or run programs as your login if it opened a specially crafted file.

Affected versions:

Ubuntu 10.10
Ubuntu 10.04 LTS
Ubuntu 8.04 LTS

Vulnerability Details:

It was discovered that Ghostscript did not correctly handle memory
allocation when parsing certain malformed JPEG-2000 images. If a user or
automated system were tricked into opening a specially crafted image, an
attacker could cause a denial of service and possibly execute arbitrary
code with user privileges. (CVE-2008-3520)

It was discovered that Ghostscript did not correctly handle certain
formatting operations when parsing JPEG-2000 images. If a user or automated
system were tricked into opening a specially crafted image, an attacker
could cause a denial of service and possibly execute arbitrary code with
user privileges. (CVE-2008-3522)

It was discovered that Ghostscript incorrectly handled certain malformed
TrueType fonts. If a user or automated system were tricked into opening a
document containing a specially crafted font, an attacker could cause a
denial of service and possibly execute arbitrary code with user privileges.
This issue only affected Ubuntu 8.04 LTS. (CVE-2009-3743)

It was discovered that Ghostscript incorrectly handled certain malformed
Type 2 fonts. If a user or automated system were tricked into opening a
document containing a specially crafted font, an attacker could cause a
denial of service and possibly execute arbitrary code with user privileges.
This issue only affected Ubuntu 8.04 LTS. (CVE-2010-4054)

Jonathan Foote discovered that Ghostscript incorrectly handled certain
malformed JPEG-2000 image files. If a user or automated system were tricked
into opening a specially crafted JPEG-2000 image file, an attacker could
cause Ghostscript to crash or possibly execute arbitrary code with user
privileges. (CVE-2011-4516, CVE-2011-4517)

Solution:
The problem can be corrected by updating your system to the following package version:

Ubuntu 10.10:
libgs8 8.71.dfsg.2-0ubuntu7.1
Ubuntu 10.04 LTS:
libgs8 8.71.dfsg.1-0ubuntu5.4
Ubuntu 8.04 LTS:
libgs8 8.61.dfsg.1-1ubuntu3.4

To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.

Ubuntu 11.10(Oneiric Ocelot) is Released ~ Upgrade Now


Recently, Ubuntu released Ubuntu 11.10.  If you interested to know how it will look like or how it works, you can take this tour. It is available in 38 language.  Ubuntu is free to use. if you haven't use ubuntu yet, then give a try now with Ubuntu
11.10.

You can download the full operating system from here:
http://www.ubuntu.com/download
or
if you have installed ubuntu 11.04 , you will be asked to upgrade to Ubuntu 11.10(that's how i come to know about it).
  
Ubuntu 11.10: Open for business
Make your IT budget go further with Ubuntu! The latest release of Ubuntu includes everything you need for your business desktop, server and cloud.

The user Interface looks good. I am curious to use it now itself but my net connection.

Few Screenshots:

Ubuntu 10.10 vulnerable to system crash and DOS attack

kernel incorrectly handled certain VLAN packets leading to a remote attacker could send specially crafted traffic to crash the system, leading to a denial of service. EFI GUID partition table was not correctly parsed leading to  A physically local attacker that could insert mountable devices could exploit this to crash the system or possibly gain root privileges.
==========================================================================
Ubuntu Security Notice USN-1220-1
September 29, 2011

linux-ti-omap4 vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 10.10

Summary:

Multiple kernel flaws have been fixed.

Software Description:
- linux-ti-omap4: Linux kernel for OMAP4

Details:

Ryan Sweat discovered that the kernel incorrectly handled certain VLAN
packets. On some systems, a remote attacker could send specially crafted
traffic to crash the system, leading to a denial of service.
(CVE-2011-1576)

Timo Warns discovered that the EFI GUID partition table was not correctly
parsed. A physically local attacker that could insert mountable devices
could exploit this to crash the system or possibly gain root privileges.
(CVE-2011-1776)

Dan Rosenberg discovered that the IPv4 diagnostic routines did not
correctly validate certain requests. A local attacker could exploit this to
consume CPU resources, leading to a denial of service. (CVE-2011-2213)

Dan Rosenberg discovered that the Bluetooth stack incorrectly handled
certain L2CAP requests. If a system was using Bluetooth, a remote attacker
could send specially crafted traffic to crash the system or gain root
privileges. (CVE-2011-2497)

Mauro Carvalho Chehab discovered that the si4713 radio driver did not
correctly check the length of memory copies. If this hardware was
available, a local attacker could exploit this to crash the system or gain
root privileges. (CVE-2011-2700)

Herbert Xu discovered that certain fields were incorrectly handled when
Generic Receive Offload (CVE-2011-2723)

Time Warns discovered that long symlinks were incorrectly handled on Be
filesystems. A local attacker could exploit this with a malformed Be
filesystem and crash the system, leading to a denial of service.
(CVE-2011-2928)

Dan Kaminsky discovered that the kernel incorrectly handled random sequence
number generation. An attacker could use this flaw to possibly predict
sequence numbers and inject packets. (CVE-2011-3188)

Darren Lavender discovered that the CIFS client incorrectly handled certain
large values. A remote attacker with a malicious server could exploit this
to crash the system or possibly execute arbitrary code as the root user.
(CVE-2011-3191)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 10.10:
linux-image-2.6.35-903-omap4 2.6.35-903.25

After a standard system update you need to reboot your computer to make
all the necessary changes.

References:
http://www.ubuntu.com/usn/usn-1220-1
CVE-2011-1576, CVE-2011-1776, CVE-2011-2213, CVE-2011-2497,
CVE-2011-2700, CVE-2011-2723, CVE-2011-2928, CVE-2011-3188,
CVE-2011-3191

Package Information:
https://launchpad.net/ubuntu/+source/linux-ti-omap4/2.6.35-903.25