| Description: | yajl-ruby is a C binding to the YAJL JSON parsing and generation
library. The 1.x branch and the 2.x branch of `yajl` contain an
integer overflow which leads to subsequent heap memory corruption when
dealing with large (~2GB) inputs. The reallocation logic at
`yajl_buf.c#L64` may result in the `need` 32bit integer wrapping to 0
when `need` approaches a value of 0x80000000 (i.e. ~2GB of data),
which results in a reallocation of buf->alloc into a small heap chunk.
These integers are declared as `size_t` in the 2.x branch of `yajl`,
which practically prevents the issue from triggering on 64bit
platforms, however this does not preclude this issue triggering on
32bit builds on which `size_t` is a 32bit integer. Subsequent
population of this under-allocated heap chunk is based on the original
buffer size, leading to heap memory corruption. This vulnerability
mostly impacts process availability. Maintainers believe exploitation
for arbitrary code execution is unlikely. A patch is available and
anticipated to be part of yajl-ruby version 1.4.2. As a workaround,
avoid passing large inputs to YAJL.
|
