A code execution vulnerability exists in the directory rehashing functionality of E2fsprogs e2fsck 1.45.4. A specially crafted ext4 directory can cause an out-of-bounds write on the stack, resulting in code execution. An attacker can corrupt a partition to trigger this vulnerability.

An exploitable code execution vulnerability exists in the quota file functionality of E2fsprogs 1.45.3. A specially crafted ext4 partition can cause an out-of-bounds write on the heap, resulting in code execution. An attacker can corrupt a partition to trigger this vulnerability.

An out-of-bounds read/write vulnerability was found in e2fsprogs 1.46.5. This issue leads to a segmentation fault and possibly arbitrary code execution via a specially crafted filesystem.

Heap-based buffer overflow in closefs.c in the libext2fs library in e2fsprogs before 1.42.12 allows local users to execute arbitrary code by causing a crafted block group descriptor to be marked as dirty. NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-0247.

A heap buffer overflow was found in e2fsprgos lib/ext2fs/openfs.c. It allows a trivial arbitrary memory write under certain conditions.

Given that fsck is affected, and that an ext2/3/4 image can force a filesystem check on mount, this will allow code execution on systems that have automount enabled by just plugging a device.

Acknowledgements:

Red Hat would like to thank oCERT for reporting these issues. oCERT acknowledges Jose Duart of the Google Security Team as the original reporter.