A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nanomemalign, nanovalloc, nanopvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

An issue in newlib v.4.3.0 allows an attacker to execute arbitrary code via the time unit scaling in the gettimeofday function.

In the multadd function of the newlib libc library, prior to versions 3.3.0 (see newlib/libc/stdlib/mprec.c), Balloc is used to allocate a big integer, however no check is performed to verify if the allocation succeeded or not. This will trigger a null pointer dereference bug in case of a memory allocation failure.

The dtoar function of the newlib libc library, prior to version 3.3.0, performs multiple memory allocations without checking their return value. This could result in NULL pointer dereference.

The REENTCHECK macro (see newlib/libc/include/sys/reent.h) as used by REENTCHECKTM, REENTCHECKMISC, REENTCHECKMP and other newlib macros in versions prior to 3.3.0, does not check for memory allocation problems when the DEBUG flag is unset (as is the case in production firmware builds).

In the lshift function of the newlib libc library, all versions prior to 3.3.0 (see newlib/libc/stdlib/mprec.c), Balloc is used to allocate a big integer, however no check is performed to verify if the allocation succeeded or not. The access to b1 will trigger a null pointer dereference bug in case of a memory allocation failure.

In the mdiff function of the newlib libc library, all versions prior to 3.3.0 (see newlib/libc/stdlib/mprec.c), Balloc is used to allocate big integers, however no check is performed to verify if the allocation succeeded or not. The access to wds and sign will trigger a null pointer dereference bug in case of a memory allocation failure.

In the i2b function of the newlib libc library, all versions prior to 3.3.0 (see newlib/libc/stdlib/mprec.c), Balloc is used to allocate a big integer, however no check is performed to verify if the allocation succeeded or not. The access of x[0] will trigger a null pointer dereference bug in case of a memory allocation failure.

In the multiply function of the newlib libc library, all versions prior to 3.3.0 (see newlib/libc/stdlib/mprec.c), Balloc is used to allocate a big integer, however no check is performed to verify if the allocation succeeded or not. The access of x[0] will trigger a null pointer dereference bug in case of a memory allocation failure.

In the d2b function of the newlib libc library, all versions prior to 3.3.0 (see newlib/libc/stdlib/mprec.c), Balloc is used to allocate a big integer, however no check is performed to verify if the allocation succeeded or not. Accessing x will trigger a null pointer dereference bug in case of a memory allocation failure.