Answer in brief
CVE-2026-64577 records a High severity (CVSS 7.5) vulnerability in gtp: check skb_pull_data() return in gtp1u_send_echo_resp(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <b3c733eaae7f362601c28ac1533d47a961cd3e1c || >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <4fc7923871d176ce0e5fecf4a9b7bb915af790ed || >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <961e9b1e33445f8e42859ecc020c9f60d8b69a8b || >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <cf45d748e437b8dd2dd987f27ee79c8c86f95c88 || >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <cd170f051dba9ac146fabcd1b91726487c0cb9fa | b3c733eaae7f362601c28ac1533d47a961cd3e1c, 4fc7923871d176ce0e5fecf4a9b7bb915af790ed, 961e9b1e33445f8e42859ecc020c9f60d8b69a8b, cf45d748e437b8dd2dd987f27ee79c8c86f95c88, cd170f051dba9ac146fabcd1b91726487c0cb9fa |
| Linux/Linuxgeneric | 5.18 | Not reported |
| Linux/Linuxgeneric | >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <9033fe49926f0e7421fefee922dc086417e905cf || >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <b3c733eaae7f362601c28ac1533d47a961cd3e1c || >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <4fc7923871d176ce0e5fecf4a9b7bb915af790ed || >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <961e9b1e33445f8e42859ecc020c9f60d8b69a8b || >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <cf45d748e437b8dd2dd987f27ee79c8c86f95c88 || >=9af41cc33471ea1efa6f77e188f055cc77d0a5c5 <cd170f051dba9ac146fabcd1b91726487c0cb9fa | 9033fe49926f0e7421fefee922dc086417e905cf, b3c733eaae7f362601c28ac1533d47a961cd3e1c, 4fc7923871d176ce0e5fecf4a9b7bb915af790ed, 961e9b1e33445f8e42859ecc020c9f60d8b69a8b, cf45d748e437b8dd2dd987f27ee79c8c86f95c88, cd170f051dba9ac146fabcd1b91726487c0cb9fa |
Published upstream
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
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
Quoted source text, attributed separately from HOL analysis.