CVE Catalog

CVE-2026-64577

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.54%

43th percentile - higher than 43% of all known CVEs

Summary

In the Linux kernel, gtp1u_send_echo_resp() ignores the return value of skb_pull_data(). When an echo request is 16-19 bytes, the call fails and returns NULL, but execution continues, leading to skb_under_panic() and kernel panic. The fix is to drop the packet when skb_pull_data() fails.

Risk Assessment

The vulnerability could allow a remote attacker to cause a kernel panic, leading to denial of service on systems with GTP enabled.

Recommendation

Apply the Linux kernel patch that checks the return value of skb_pull_data() and drops the packet on failure. Update the kernel to a version containing this fix.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: gtp: check skb_pull_data() return in gtp1u_send_echo_resp() gtp1u_send_echo_resp() ignores skb_pull_data()'s return value. Its caller gtp1u_udp_encap_recv() only guarantees 16 bytes (udphdr + gtp1_header), but the pull requests 20 (gtp1_header_long + udphdr). For a 16-19 byte echo request the pull fails and returns NULL without advancing skb->data; execution continues, and the following skb_push() plus the IP header pushed by iptunnel_xmit() move skb->data below skb->head, tripping skb_under_panic(). Fix it by dropping the packet when skb_pull_data() fails. skbuff: skb_under_panic: ... kernel BUG at net/core/skbuff.c:214! Call Trace: skb_push (net/core/skbuff.c:2648) iptunnel_xmit (net/ipv4/ip_tunnel_core.c:82) gtp_encap_recv (drivers/net/gtp.c:701 drivers/net/gtp.c:808 drivers/net/gtp.c:920) udp_queue_rcv_one_skb (net/ipv4/udp.c:2388) ... Kernel panic - not syncing: Fatal exception in interrupt

Vulnerability data from NVD (NIST) · CISA KEV · EPSS