CVE-2018-1000030 Use after free in n/a
Race condition in Python threading allows heap buffer overflow and use-after-free, potentially enabling code execution or privilege escalation in multi-threaded environments.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2018-1000030?
CVE-2018-1000030 is a low-severity use after free vulnerability in Canonical Ubuntu Linux, published on 8 Feb 2018. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Python 2.7.14 is vulnerable to a Heap-Buffer-Overflow as well as a Heap-Use-After-Free. Python versions prior to 2.7.14 may also be vulnerable and it appears that Python 2.7.17 and prior may also be vulnerable however this has not been confirmed. The vulnerability lies when multiply threads are handling large amounts of data. In both cases there is essentially a race condition that occurs. For the Heap-Buffer-Overflow, Thread 2 is creating the size for a buffer, but Thread1 is already writing to the buffer without knowing how much to write. So when a large amount of data is being processed, it is very easy to cause memory corruption using a Heap-Buffer-Overflow. As for the Use-After-Free, Thread3->Malloc->Thread1->Free's->Thread2-Re-uses-Free'd Memory. The PSRT has stated that this is not a security vulnerability due to the fact that the attacker must be able to run code, however in some situations, such as function as a service, this vulnerability can potentially be used by an attacker to violate a trust boundary, as such the DWF feels this issue deserves a CVE.
Which versions are affected by CVE-2018-1000030?
It affects 2 products.
Products include Canonical Ubuntu Linux, Python Python.
How do I fix CVE-2018-1000030?
Upgrade to a fixed version.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2018-1000030 being exploited?
There is no known exploitation of CVE-2018-1000030 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Canonical Ubuntu Linux
Sources
Also known as AZL-109623, DEBIAN-CVE-2018-1000030, GHSA-rwj4-fxr5-gh64, PSF-2018-2, UBUNTU-CVE-2018-1000030.