{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-99121 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-99121 is a vulnerability in Linux, published on 28 Oct 2026."},"fix_prompt":"Check this codebase for CVE-2026-99121 and fix it if it is affected.\n\nWhat it is: CVE-2026-99121 is a vulnerability in Linux, published on 28 Oct 2026. \nExploitation: There is no known exploitation of CVE-2026-99121 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-2026-99121/ (Markdown: https://insights.sbomify.com/CVE-2026-99121/index.md)","id":"CVE-2026-99121","markdown":"https://insights.sbomify.com/CVE-2026-99121/index.md","name":"CVE-2026-99121","record":{"aliases":["AZL-111221","BELL-CVE-2026-99121","DEBIAN-CVE-2026-99121","GHSA-6q9r-cqw9-q9q4","UBUNTU-CVE-2026-99121"],"analysis":null,"analysis_generated_by":null,"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\nipv4: avoid divide by zero in fib_rebalance\n\nfib_rebalance() computes the total eligible nexthop weight in one pass\nand programs upper bounds in a second pass. A concurrent change to\nignore_routes_with_linkdown can make the first pass return zero while\nthe second pass sees an eligible nexthop, resulting in division by zero.\n\nIf the first pass reports a zero total, set each nexthop upper bound to\n-1 and skip the division. This matches the IPv6 fix in commit\nd2c26c2911dd (\"ipv6: avoid divide by zero in rt6_multipath_rebalance\")\nand preserves the lock-free rebalance path.","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":"ipv4: avoid divide by zero in fib_rebalance","id":"CVE-2026-99121","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":null,"year":"2026"},"n_packages":0,"n_references":3,"next":{"headline":"vsock/vmci: validate packet source for connected sockets","id":"CVE-2026-99122"},"packages":[],"prev":{"headline":"KVM: x86/mmu: Cope with the SS bit being set in #NPF exit codes","id":"CVE-2026-99120"},"products":["Linux"],"published":"2026-10-28","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":"2026-10-28","vendors":["Linux"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2026-99121/"}