Ubuntu: (CVE-2021-46935): linux vulnerability
Description
In the Linux kernel, the following vulnerability has been resolved: binder: fix async_free_space accounting for empty parcels In 4.13, commit 74310e06be4d ("android: binder: Move buffer out of area shared with user space") fixed a kernel structure visibility issue. As part of that patch, sizeof(void *) was used as the buffer size for 0-length data payloads so the driver could detect abusive clients sending 0-length asynchronous transactions to a server by enforcing limits on async_free_size. Unfortunately, on the "free" side, the accounting of async_free_space did not add the sizeof(void *) back. The result was that up to 8-bytes of async_free_space were leaked on every async transaction of 8-bytes or less. These small transactions are uncommon, so this accounting issue has gone undetected for several years. The fix is to use "buffer_size" (the allocated buffer size) instead of "size" (the logical buffer size) when updating the async_free_space during the free operation. These are the same except for this corner case of asynchronous transactions with payloads < 8 bytes.
Solution(s)
- ubuntu-upgrade-linux
- ubuntu-upgrade-linux-aws
- ubuntu-upgrade-linux-aws-5-4
- ubuntu-upgrade-linux-aws-hwe
- ubuntu-upgrade-linux-azure
- ubuntu-upgrade-linux-azure-4-15
- ubuntu-upgrade-linux-azure-5-4
- ubuntu-upgrade-linux-bluefield
- ubuntu-upgrade-linux-gcp
- ubuntu-upgrade-linux-gcp-4-15
- ubuntu-upgrade-linux-gcp-5-4
- ubuntu-upgrade-linux-gkeop
- ubuntu-upgrade-linux-hwe
- ubuntu-upgrade-linux-hwe-5-4
- ubuntu-upgrade-linux-ibm
- ubuntu-upgrade-linux-ibm-5-4
- ubuntu-upgrade-linux-kvm
- ubuntu-upgrade-linux-oracle
- ubuntu-upgrade-linux-oracle-5-4
- ubuntu-upgrade-linux-raspi
- ubuntu-upgrade-linux-raspi-5-4
- Lightweight Endpoint Agent
- Live Dashboards
- Real Risk Prioritization
- IT-Integrated Remediation Projects
- Cloud, Virtual, and Container Assessment
- Integrated Threat Feeds
- Easy-to-Use RESTful API
- Automation-Assisted Patching
- Automated Containment
With Rapid7 live dashboards, I have a clear view of all the assets on my network, which ones can be exploited, and what I need to do in order to reduce the risk in my environment in real-time. No other tool gives us that kind of value and insight.
– Scott Cheney, Manager of Information Security, Sierra View Medical Center