CVE-2019-12900

La función BZ2_decompress en el archivo decompress.c en bzip2 hasta 1.0.6, presenta una escritura fuera de límites cuando hay muchos selectores.

A data integrity error was found in the bzip2 (User-space package) functionality when decompressing. This issue occurs when a user decompresses a particular kind of .bz2 files. A local user could get unexpected results (or corrupted data) as result of decompressing these files.

The decompressor used in bzip2 contains a bug which can lead to an out-of-bounds write when processing a specially crafted bzip2(1) file. bzip2recover contains a heap use-after-free bug which can be triggered when processing a specially crafted bzip2(1) file. An attacker who can cause maliciously crafted input to be processed may trigger either of these bugs. The bzip2recover bug may cause a crash, permitting a denial-of-service. The bzip2 decompressor bug could potentially be exploited to execute arbitrary code. Note that some utilities, including the tar(1) archiver and the bspatch(1) binary patching utility (used in portsnap(8) and freebsd-update(8)) decompress bzip2(1)-compressed data internally; system administrators should assume that their systems will at some point decompress bzip2(1)-compressed data even if they never explicitly invoke the bunzip2(1) utility.