{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-99074 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-99074 is a vulnerability in Linux, published on 23 Oct 2026."},"fix_prompt":"Check this codebase for CVE-2026-99074 and fix it if it is affected.\n\nWhat it is: CVE-2026-99074 is a vulnerability in Linux, published on 23 Oct 2026. \nExploitation: There is no known exploitation of CVE-2026-99074 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-2026-99074/ (Markdown: https://insights.sbomify.com/CVE-2026-99074/index.md)","id":"CVE-2026-99074","markdown":"https://insights.sbomify.com/CVE-2026-99074/index.md","name":"CVE-2026-99074","record":{"aliases":["BELL-CVE-2026-99074","DEBIAN-CVE-2026-99074","GHSA-j9w6-p85x-r6r9","UBUNTU-CVE-2026-99074"],"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: stop PMTU walk when nexthop group shrinks\n\nCommit 7d3f3b4367f3 (\"net: ipv4: Cache pmtu for all packet paths if\nmultipath enabled\") made __ip_rt_update_pmtu() update every path.\n\nFor nexthop objects, fib_info_num_path() and fib_info_nhc()\nindependently load nh-\u003enh_grp.  RCU protects each group's lifetime but\ndoes not make the loads observe the same group.  If replacement shrinks\nthe group after the loop accepts an index, fib_info_nhc() returns NULL\nand update_or_create_fnhe() dereferences it.\n\nA deterministic probe only widened the existing window between the real\noperations.  On v7.2, an RTM_NEWNEXTHOP replacement published a\none-member group after the PMTU reader accepted index 1 from a two-member\ngroup, producing:\n\n  KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n  RIP: update_or_create_fnhe+0x45/0x15b0\n\nStop when the indexed path is absent.  Groups are dense, so no later\nindex exists in that snapshot.  The same real-writer window completed\n114,423 PMTU iterations without an oops with this check.  A reproducer\nis available on request.\n\nReplacement requires CAP_NET_ADMIN in the network namespace.  Where\nunprivileged user namespaces are permitted, a local user can obtain it\nin a new user and network namespace.","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: stop PMTU walk when nexthop group shrinks","id":"CVE-2026-99074","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":null,"year":"2026"},"n_packages":0,"n_references":5,"next":{"headline":"rust_binder: reschedule node refcount update on thread exit","id":"CVE-2026-99075"},"packages":[],"prev":{"headline":"ipv4: stop exception dump when nexthop group shrinks","id":"CVE-2026-99073"},"products":["Linux"],"published":"2026-10-23","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":"2026-10-23","vendors":["Linux"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2026-99074/"}