{"id":24447,"date":"2026-09-16T20:32:19","date_gmt":"2026-09-16T12:32:19","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-89790"},"modified":"2026-09-16T20:32:19","modified_gmt":"2026-09-16T12:32:19","slug":"cve-2026-89790","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-89790","title":{"rendered":"CVE-2026-89790 &#8211; In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: avoid divide by"},"content":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>ipv6: avoid divide by zero in rt6_multipath_rebalance<\/p>\n<p>rt6_multipath_rebalance() calculates the total eligible nexthop weight<br \/>\nin one pass and programs upper bounds in a second pass. Since<br \/>\nRTM_NEWROUTE is RTNL-free, a concurrent<br \/>\nignore_routes_with_linkdown update can make the first pass return zero<br \/>\nwhile the second sees an eligible nexthop, causing<br \/>\nrt6_upper_bound_set() to divide by zero.<\/p>\n<p>UBSAN: division-overflow in net\/ipv6\/route.c:4845:17<br \/>\nOops: divide error: 0000 [#1] SMP KASAN NOPTI<br \/>\n  rt6_upper_bound_set() net\/ipv6\/route.c:4845<br \/>\n  rt6_multipath_rebalance()<br \/>\n  fib6_add_rt2node()<br \/>\n  ip6_route_multipath_add()<br \/>\n  inet6_rtm_newroute()<\/p>\n<p>Skip upper-bound calculation when the first pass reports a zero total.<br \/>\nThis respects the lock-free performance considerations here and solves<br \/>\ninsecure scenarios.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In the Linux kernel, the following vulnerability has been resolved:<\/p>\n<p>ipv6: avoid divide by zero in rt6_multipath_rebalance<\/p>\n<p>rt6_multipath_rebalance() calculates the total eligible nexthop weight<br \/>\nin on<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-24447","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/24447","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=24447"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=24447"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=24447"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}