GHSA-CQ6P-33CJ-VGHC
Vulnerability from github – Published: 2026-08-05 09:31 – Updated: 2026-08-19 18:32In 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
{
"affected": [],
"aliases": [
"CVE-2026-64577"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-05T08:16:37Z",
"severity": "HIGH"
},
"details": "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()\u0027s 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-\u003edata; execution continues, and the following skb_push()\nplus the IP header pushed by iptunnel_xmit() move skb-\u003edata below\nskb-\u003ehead, 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",
"id": "GHSA-cq6p-33cj-vghc",
"modified": "2026-08-19T18:32:03Z",
"published": "2026-08-05T09:31:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64577"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4fc7923871d176ce0e5fecf4a9b7bb915af790ed"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9033fe49926f0e7421fefee922dc086417e905cf"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/961e9b1e33445f8e42859ecc020c9f60d8b69a8b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b3c733eaae7f362601c28ac1533d47a961cd3e1c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/cd170f051dba9ac146fabcd1b91726487c0cb9fa"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/cf45d748e437b8dd2dd987f27ee79c8c86f95c88"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.