{"id":"CVE-2026-64577","title":"In the Linux kernel, the following vulnerability has been resolved:\n\ngtp: check skb_pull_data() return in gtp1u_send_echo_resp()\n\ngtp1u_send_echo_resp() ignores skb_pull_data()'s return value","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ngtp: check skb_pull_data() return in gtp1u_send_echo_resp()\n\ngtp1u_send_echo_resp() ignores skb_pull_data()'s return value. Its\ncaller gtp1u_udp_encap_recv() only guara…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","published":"2026-08-05","updated":"2026-08-08","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64577","references":[{"url":"https://git.kernel.org/stable/c/4fc7923871d176ce0e5fecf4a9b7bb915af790ed","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/961e9b1e33445f8e42859ecc020c9f60d8b69a8b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b3c733eaae7f362601c28ac1533d47a961cd3e1c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cd170f051dba9ac146fabcd1b91726487c0cb9fa","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cf45d748e437b8dd2dd987f27ee79c8c86f95c88","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd"],"epss":0.00576,"epssPercentile":0.46204,"ingestedAt":"2026-08-08T20:29:49.387Z","slug":"CVE-2026-64577","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ngtp: check skb_pull_data() return in gtp1u_send_echo_resp()\n\ngtp1u_send_echo_resp() ignores skb_pull_data()'s return value. Its\ncaller gtp1u_udp_encap_recv() only guarantees 16 bytes (udphdr +\ngtp1_header), but the pull requests 20 (gtp1_header_long + udphdr). For\na 16-19 byte echo request the pull fails and returns NULL without\nadvancing skb->data; execution continues, and the following skb_push()\nplus the IP header pushed by iptunnel_xmit() move skb->data below\nskb->head, tripping skb_under_panic().\n\nFix it by dropping the packet when skb_pull_data() fails.\n\n  skbuff: skb_under_panic: ...\n  kernel BUG at net/core/skbuff.c:214!\n  Call Trace:\n   skb_push (net/core/skbuff.c:2648)\n   iptunnel_xmit (net/ipv4/ip_tunnel_core.c:82)\n   gtp_encap_recv (drivers/net/gtp.c:701 drivers/net/gtp.c:808 drivers/net/gtp.c:920)\n   udp_queue_rcv_one_skb (net/ipv4/udp.c:2388)\n   ...\n  Kernel panic - not syncing: Fatal exception in interrupt\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}