{"id":"CVE-2026-63993","summary":"vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nvxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()\n\nskb_tunnel_check_pmtu() can change skb-\u003ehead.\n\nReusing old_iph afer skb_tunnel_check_pmtu() can cause an UAF.\n\nUse instead ip_hdr(skb) as done in drivers/net/bareudp.c\nand drivers/net/geneve.c.\n\nFound by Sashiko.","modified":"2026-07-22T03:31:42.359433300Z","published":"2026-07-19T14:56:13.218Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63993.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/5303925e360527243b46a440a04667826bbc72b7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/609e63312c29aad18026a1d3222e123d4b6b0feb"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6b8bfce9d2f774d2c2243e0248e03efb99bba6c0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7d9ef0cb271555d8cf39fefe6c981e1493b25ecf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8d435d68d71fb875876b722f4136caf74f2f48bd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9257f56ac47ef1976bcd056cf986a9988eeec67a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a493efd4336cf19122ae0e4cbb3d31b32d70deea"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dc3bfa050f873371e745bdf478b1f5b738e5733d"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63993.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63993"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"4cb47a8644cc9eb8ec81190a50e79e6530d0297f"},{"fixed":"6b8bfce9d2f774d2c2243e0248e03efb99bba6c0"},{"fixed":"9257f56ac47ef1976bcd056cf986a9988eeec67a"},{"fixed":"8d435d68d71fb875876b722f4136caf74f2f48bd"},{"fixed":"dc3bfa050f873371e745bdf478b1f5b738e5733d"},{"fixed":"609e63312c29aad18026a1d3222e123d4b6b0feb"},{"fixed":"5303925e360527243b46a440a04667826bbc72b7"},{"fixed":"a493efd4336cf19122ae0e4cbb3d31b32d70deea"},{"fixed":"7d9ef0cb271555d8cf39fefe6c981e1493b25ecf"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-63993.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.9.0"},{"fixed":"5.10.259"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.210"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.176"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.143"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.93"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.35"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.12"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-63993.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}