{"cve":"CVE-2026-98240","nvd":{"published":"2026-10-06T09:18:11.960","modified":"2026-10-19T10:18:24.877","status":"Received","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.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/0f6a6beb01c068fcd5274eabf22c260039749fea","https://git.kernel.org/stable/c/455ebeadf714f51e1dbbd6a022c74c9215b1cd76","https://git.kernel.org/stable/c/9907325257b4b382f26aafd5d9a8d47915907dd5"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:57:46.668721662+00:00"},"epss":{"cve":"CVE-2026-98240","score":0.00183,"percentile":0.07844,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}