Bookkeeping errors when extending the read-ahead buffer when trying to identify an mtree archive could lead libarchive to significantly overcalculate the size of the line being read, resulting in heap out-of-bounds reads or a crash. Disclosed on oss-security: http://seclists.org/oss-sec/2016/q3/516 Upstream issue: https://github.com/libarchive/libarchive/issues/747 Upstream fix: https://github.com/libarchive/libarchive/commit/eec077f All the mtree-related crashes in the oss-sec post came from the same underlying issue and were resolved in this commit.
This could conceivably be exploited for controlled read of the heap, but code execution is not possible.
Created libarchive tracking bugs for this issue: Affects: fedora-all [bug 1378669]
Statement: Red Hat Product Security has rated this issue as having Low security impact. This issue is not currently planned to be addressed in future updates. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.
*** Bug 1385664 has been marked as a duplicate of this bug. ***