{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-89790 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-89790 is a denial of service vulnerability in Linux, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-89790 and fix it if it is affected.\n\nWhat it is: CVE-2026-89790 is a denial of service vulnerability in Linux, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-89790 in the wild and no public exploit code.\n\nAffected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-89790/ (Markdown: https://insights.sbomify.com/CVE-2026-89790/index.md)","id":"CVE-2026-89790","markdown":"https://insights.sbomify.com/CVE-2026-89790/index.md","name":"CVE-2026-89790","record":{"aliases":["BELL-CVE-2026-89790","DEBIAN-CVE-2026-89790","GHSA-8437-c9wr-2522","UBUNTU-CVE-2026-89790"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel","requires_auth":"none","summary":"A race condition in the Linux kernel IPv6 routing code can cause a divide-by-zero error, leading to a system crash.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: avoid divide by zero in rt6_multipath_rebalance\n\nrt6_multipath_rebalance() calculates the total eligible nexthop weight\nin one pass and programs upper bounds in a second pass. Since\nRTM_NEWROUTE is RTNL-free, a concurrent\nignore_routes_with_linkdown update can make the first pass return zero\nwhile the second sees an eligible nexthop, causing\nrt6_upper_bound_set() to divide by zero.\n\nUBSAN: division-overflow in net/ipv6/route.c:4845:17\nOops: divide error: 0000 [#1] SMP KASAN NOPTI\n  rt6_upper_bound_set() net/ipv6/route.c:4845\n  rt6_multipath_rebalance()\n  fib6_add_rt2node()\n  ip6_route_multipath_add()\n  inet6_rtm_newroute()\n\nSkip upper-bound calculation when the first pass reports a zero total.\nThis respects the lock-free performance considerations here and solves\ninsecure scenarios.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"ipv6: avoid divide by zero in rt6_multipath_rebalance","id":"CVE-2026-89790","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":3,"next":{"headline":"perf: Fix use-after-free when perf mmap() revival races with the last munmap()","id":"CVE-2026-89791"},"packages":[],"prev":{"headline":"gtp: add synchronize_net() in gtp_newlink() error path to prevent use-after-free","id":"CVE-2026-89789"},"products":["Linux"],"published":"2026-09-16","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"A race condition in the Linux kernel IPv6 routing code can cause a divide-by-zero error, leading to a system crash.","url":"https://insights.sbomify.com/CVE-2026-89790/"}