{"api_version":"1","generated_at":"2026-10-08T09:39:04+00:00","cve":"CVE-2026-98240","urls":{"html":"https://cve.report/CVE-2026-98240","api":"https://cve.report/api/cve/CVE-2026-98240.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98240","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98240"},"summary":{"title":"net: ip_tunnel: initialize `options_len` before referencing options","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ip_tunnel: initialize `options_len` before referencing options\n\nThe following command triggers a kernel panic:\n\n  ip link add d0 type dummy; ip link set d0 up\n  ip route add 10.30.0.0/16 \\\n    encap ip id 300 geneve_opts 4660:66:11223344 dev d0\n\n  memcpy: detected buffer overflow: 4 byte write of buffer size 0\n  kernel BUG at lib/string_helpers.c:1044!\n  ...\n  ip_tun_parse_opts.part.0.cold+0x10/0x10\n  ip_tun_build_state+0x116/0x2a0\n\nOn kernels built with GCC 15+ and `CONFIG_FORTIFY_SOURCE`, the fortified\n`memcpy()` got 0 sized destination with request of 4 bytes length:\n\n  static int ip_tun_parse_opts_geneve(...)\n  {\n      ...\n      attr = tb[LWTUNNEL_IP_OPT_GENEVE_DATA];\n      data_len = nla_len(attr); /* == 4 */\n\n      struct geneve_opt *opt = ip_tunnel_info_opts(info) + opts_len;\n      memcpy(opt->opt_data, nla_data(attr), data_len);\n      /*     ^^^^^^^^^^^^^ 0 since options_len is assigned afterwards */\n\nFixed by initializing the counter before the options are referenced.\nMatching what `tunnel_key_opts_set()` already does.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-06 09:18:11","updated_at":"2026-10-06 09:18:11"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/9907325257b4b382f26aafd5d9a8d47915907dd5","name":"https://git.kernel.org/stable/c/9907325257b4b382f26aafd5d9a8d47915907dd5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/455ebeadf714f51e1dbbd6a022c74c9215b1cd76","name":"https://git.kernel.org/stable/c/455ebeadf714f51e1dbbd6a022c74c9215b1cd76","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/0f6a6beb01c068fcd5274eabf22c260039749fea","name":"https://git.kernel.org/stable/c/0f6a6beb01c068fcd5274eabf22c260039749fea","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98240","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98240","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected bb5e62f2d547c4de6d1b144cbce2373a76c33f18 9907325257b4b382f26aafd5d9a8d47915907dd5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected bb5e62f2d547c4de6d1b144cbce2373a76c33f18 0f6a6beb01c068fcd5274eabf22c260039749fea git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected bb5e62f2d547c4de6d1b144cbce2373a76c33f18 455ebeadf714f51e1dbbd6a022c74c9215b1cd76 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.15","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.15 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.54 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.8 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc4 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"98240","cve":"CVE-2026-98240","epss":"0.002230000","percentile":"0.118350000","score_date":"2026-10-06","updated_at":"2026-10-07 00:14:55"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/ipv4/ip_tunnel_core.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"9907325257b4b382f26aafd5d9a8d47915907dd5","status":"affected","version":"bb5e62f2d547c4de6d1b144cbce2373a76c33f18","versionType":"git"},{"lessThan":"0f6a6beb01c068fcd5274eabf22c260039749fea","status":"affected","version":"bb5e62f2d547c4de6d1b144cbce2373a76c33f18","versionType":"git"},{"lessThan":"455ebeadf714f51e1dbbd6a022c74c9215b1cd76","status":"affected","version":"bb5e62f2d547c4de6d1b144cbce2373a76c33f18","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/ipv4/ip_tunnel_core.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.15"},{"lessThan":"6.15","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.54","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.8","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc4","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.54","versionStartIncluding":"6.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.8","versionStartIncluding":"6.15","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc4","versionStartIncluding":"6.15","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ip_tunnel: initialize `options_len` before referencing options\n\nThe following command triggers a kernel panic:\n\n  ip link add d0 type dummy; ip link set d0 up\n  ip route add 10.30.0.0/16 \\\n    encap ip id 300 geneve_opts 4660:66:11223344 dev d0\n\n  memcpy: detected buffer overflow: 4 byte write of buffer size 0\n  kernel BUG at lib/string_helpers.c:1044!\n  ...\n  ip_tun_parse_opts.part.0.cold+0x10/0x10\n  ip_tun_build_state+0x116/0x2a0\n\nOn kernels built with GCC 15+ and `CONFIG_FORTIFY_SOURCE`, the fortified\n`memcpy()` got 0 sized destination with request of 4 bytes length:\n\n  static int ip_tun_parse_opts_geneve(...)\n  {\n      ...\n      attr = tb[LWTUNNEL_IP_OPT_GENEVE_DATA];\n      data_len = nla_len(attr); /* == 4 */\n\n      struct geneve_opt *opt = ip_tunnel_info_opts(info) + opts_len;\n      memcpy(opt->opt_data, nla_data(attr), data_len);\n      /*     ^^^^^^^^^^^^^ 0 since options_len is assigned afterwards */\n\nFixed by initializing the counter before the options are referenced.\nMatching what `tunnel_key_opts_set()` already does."}],"providerMetadata":{"dateUpdated":"2026-10-06T08:45:11.284Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/9907325257b4b382f26aafd5d9a8d47915907dd5"},{"url":"https://git.kernel.org/stable/c/0f6a6beb01c068fcd5274eabf22c260039749fea"},{"url":"https://git.kernel.org/stable/c/455ebeadf714f51e1dbbd6a022c74c9215b1cd76"}],"title":"net: ip_tunnel: initialize `options_len` before referencing options","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98240","datePublished":"2026-10-06T08:45:11.284Z","dateReserved":"2026-09-25T10:25:14.329Z","dateUpdated":"2026-10-06T08:45:11.284Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-06 09:18:11","lastModifiedDate":"2026-10-06 09:18:11","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98240","Ordinal":"1","Title":"net: ip_tunnel: initialize `options_len` before referencing opti","CVE":"CVE-2026-98240","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98240","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ip_tunnel: initialize `options_len` before referencing options\n\nThe following command triggers a kernel panic:\n\n  ip link add d0 type dummy; ip link set d0 up\n  ip route add 10.30.0.0/16 \\\n    encap ip id 300 geneve_opts 4660:66:11223344 dev d0\n\n  memcpy: detected buffer overflow: 4 byte write of buffer size 0\n  kernel BUG at lib/string_helpers.c:1044!\n  ...\n  ip_tun_parse_opts.part.0.cold+0x10/0x10\n  ip_tun_build_state+0x116/0x2a0\n\nOn kernels built with GCC 15+ and `CONFIG_FORTIFY_SOURCE`, the fortified\n`memcpy()` got 0 sized destination with request of 4 bytes length:\n\n  static int ip_tun_parse_opts_geneve(...)\n  {\n      ...\n      attr = tb[LWTUNNEL_IP_OPT_GENEVE_DATA];\n      data_len = nla_len(attr); /* == 4 */\n\n      struct geneve_opt *opt = ip_tunnel_info_opts(info) + opts_len;\n      memcpy(opt->opt_data, nla_data(attr), data_len);\n      /*     ^^^^^^^^^^^^^ 0 since options_len is assigned afterwards */\n\nFixed by initializing the counter before the options are referenced.\nMatching what `tunnel_key_opts_set()` already does.","Type":"Description","Title":"net: ip_tunnel: initialize `options_len` before referencing opti"}]}}}