{"cve":"CVE-2026-64577","nvd":{"published":"2026-08-05T08:16:37.630","modified":"2026-08-19T17:20:17.690","status":"Received","description":"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 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","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":[],"references":["https://git.kernel.org/stable/c/4fc7923871d176ce0e5fecf4a9b7bb915af790ed","https://git.kernel.org/stable/c/9033fe49926f0e7421fefee922dc086417e905cf","https://git.kernel.org/stable/c/961e9b1e33445f8e42859ecc020c9f60d8b69a8b","https://git.kernel.org/stable/c/b3c733eaae7f362601c28ac1533d47a961cd3e1c","https://git.kernel.org/stable/c/cd170f051dba9ac146fabcd1b91726487c0cb9fa"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:47:10.050265369+00:00"},"epss":{"cve":"CVE-2026-64577","score":0.00576,"percentile":0.47504,"date":"2026-10-31"},"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."]}