GNU Tar through 1.30, when --sparse is used, mishandles file shrinkage during read access, which allows local users to cause a denial of service (infinite read loop in sparse_dump_region in sparse.c) by modifying a file that is supposed to be archived by a different user's process (e.g., a system backup running as root).
Upstream Patch: http://git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42c
The bug has been referenced in the following commit(s):
Author: Lars Wendler <firstname.lastname@example.org>
AuthorDate: 2019-01-01 14:36:33 +0000
Commit: Lars Wendler <email@example.com>
CommitDate: 2019-01-01 14:38:01 +0000
app-arch/tar: Revbump to fix CVE-2018-20482
Patch added without new test suite because that would require
an eautoreconf run.
Package-Manager: Portage-2.3.53, Repoman-2.3.12
Signed-off-by: Lars Wendler <firstname.lastname@example.org>
app-arch/tar/files/tar-1.30-CVE-2018-20482.patch | 146 +++++++++++++++++++++++
app-arch/tar/tar-1.30-r1.ebuild | 82 +++++++++++++
2 files changed, 228 insertions(+)
Let's go with =app-arch/tar-1.31 which has additional buffer overflow fixes.
please test and mark stable: =app-arch/tar-1.31
This issue was resolved and addressed in
GLSA 201903-05 at https://security.gentoo.org/glsa/201903-05
by GLSA coordinator Aaron Bauman (b-man).