View at Official ubuntu advisory, NVD, CVE.org · CVE detail
Freshness: upstream tracker timestamp is available; use API updated time as primary recency signal.
CVE-2018-20482 low priority: Ubuntu including 1 source packages (tar), 9 status rows across 9 suites (bionic, cosmic, disco, eoan, focal, groovy, trusty, upstream, xenial): not-affected 4, released 4, ignored 1.
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).