#amd

This blog post outlines the work that Microsoft is doing to eliminate uninitialized stack memory vulnerabilities from Windows and why we’re on this path. This blog post will be broken down into a few parts that folks can jump to: Uninitialized Memory Background Potential Solutions to Uninitialized Memory Vulnerabilities InitAll – Automatic Initialization Interesting Findings with InitAll Performance Optimizations Impact for Customers Forward Looking Plans None of this work would have been possible without close partnership between the Visual Studio organization, the Windows organization, and MSRC.

The fix for CVE-2019-11599 was not complete. A local user could use this flaw to obtain sensitive information, cause a denial of service, or possibly have other unspecified impacts by triggering a race condition with mmget_not_zero or get_task_mm calls.

An array overflow was discovered in mt76_add_fragment in drivers/net/wireless/mediatek/mt76/dma.c in the Linux kernel before 5.5.10, aka CID-b102f0c522cf. An oversized packet with too many rx fragments can corrupt memory of adjacent pages.

In FreeBSD 12.1-STABLE before r356035, 12.1-RELEASE before 12.1-RELEASE-p4, 11.3-STABLE before r356036, and 11.3-RELEASE before 11.3-RELEASE-p8, incomplete packet data validation may result in accessing out-of-bounds memory leading to a kernel panic or other unpredictable results.

An exploitable signed comparison vulnerability exists in the ARMv7 memcpy() implementation of GNU glibc 2.30.9000. Calling memcpy() (on ARMv7 targets that utilize the GNU glibc implementation) with a negative value for the 'num' parameter results in a signed comparison vulnerability. If an attacker underflows the 'num' parameter to memcpy(), this vulnerability could lead to undefined behavior such as writing to out-of-bounds memory and potentially remote code execution. Furthermore, this memcpy() implementation allows for program execution to continue in scenarios where a segmentation fault or crash should have occurred. The dangers occur in that subsequent execution and iterations of this code will be executed with this corrupted data.

OpenSMTPD before 6.6.4 allows remote code execution because of an out-of-bounds read in mta_io in mta_session.c for multi-line replies. Although this vulnerability affects the client side of OpenSMTPD, it is possible to attack a server because the server code launches the client code during bounce handling.

OpenBSD through 6.6 allows local users to escalate to root because a check for LD_LIBRARY_PATH in setuid programs can be defeated by setting a very small RLIMIT_DATA resource limit. When executing chpass or passwd (which are setuid root), _dl_setup_env in ld.so tries to strip LD_LIBRARY_PATH from the environment, but fails when it cannot allocate memory. Thus, the attacker is able to execute their own library code as root.

An exploitable out-of-bounds write vulnerability exists in the igcore19d.dll PNG header-parser of the Accusoft ImageGear 19.3.0 library. A specially crafted PNG file can cause an out-of-bounds write, resulting in a remote code execution. An attacker needs to provide a malformed file to the viction to trigger the vulnerability.

An exploitable out-of-bounds write vulnerability exists in the igcore19d.dll TIFdecodethunderscan function of Accusoft ImageGear 19.3.0 library. A specially crafted TIFF file can cause an out of bounds write, resulting in a remote code execution. An attacker needs to provide a malformed file to the victim to trigger the vulnerability.

In the Linux kernel before 5.3.9, there is a use-after-free bug that can be caused by a malicious USB device in the drivers/nfc/pn533/usb.c driver, aka CID-6af3aa57a098.